The Armoloy Corporation is an innovative, US-based metal finishing company specializing in thin dense chrome and coatings application engineering. This franchising organization is equipped with an in-house metallurgical and chemical testing laboratory that focuses on the research and development of new coating technologies and applications.
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The Armoloy Corporation helps Improve metal surface performance to its highest pinnacle. Whether you’re already a partner or interested in learning more about us, we’re here to help answer any questions you may have. View a list of some of the most common questions we receive below.
Metal treating is a broad term that refers to a variety of processes used to modify the surface and internal properties of metals to enhance performance in specific applications. This includes heat treatment, surface coatings, plating, and other chemical or mechanical methods. Metal treating is used to improve a metal’s hardness, strength, corrosion resistance, wear resistance, and other characteristics.
Common methods of metal treating include:
- Heat Treatment: Processes like hardening, annealing, tempering, and quenching alter the internal structure of the metal to enhance properties like hardness and ductility.
- Surface Coating and Plating: Techniques such as electroplating, thermal spraying, and vapor deposition apply a protective or functional coating to the metal surface. These treatments are often used to improve corrosion resistance or wear resistance.
- Chemical Treatments: Methods like carburizing or nitriding involve adding elements like carbon or nitrogen to the surface of metals to change their surface composition, improving hardness and fatigue resistance.
The Armoloy Corporation performs all chemical, mechanical, and corrosion testing in our in-house laboratory. Armoloy also partners with 3rd party laboratories for additional testing methods when necessary.
The Armoloy Network includes 15 facilities in North America, Europe, Asia, and Africa. Armoloy is constantly expanding its service offerings with facilities strategically placed for fast lead times and efficient delivery to anywhere across the globe. Find a full list of our U.S. and international processing facilities by visiting our Licensed Processing Facilities page. Please contact us with any related questions.
Thin Dense Chrome (TDC) can be applied to most ferrous and non-ferrous alloys. Thin Dense Chrome is not recommended for aluminum, magnesium, and titanium substrates without an intermediate layer. However, Armoloy’s Bi-Protec® and ALCOAT® are exceptional alternative coating technologies for plating on aluminum substrates and offer unparalleled performance in wear and corrosion protection in the most unforgiving environments.
The Armoloy Corporation operates a total of 15 processing fulfillment facilities worldwide. This includes:
- 9 licensed facilities across 7 U.S. states, offering regional coating services and fast turnaround.
- 6 international facilities located in 6 different countries, spanning North America, Europe, and Asia.
Armoloy offers two separate process development facilities within the United States that work in partnership with our innovation center. They are located in DeKalb, Illinois and Providence, Rhode Island.
Yes, we are happy to work with suppliers to choose the right coating, develop a robust process, and identify the ideal processing partner to fit any application. Learn more about our process on our How It Works page.
Metal coatings are used to impart a variety of properties to components that aren’t otherwise present in the base metal itself. These properties can include improved wear, corrosion, or chemical resistance, they can be applied for aesthetic reasons, to help to reduce friction, fretting, and galling, or for a variety of other reasons. Coatings can be a cost-effective way of meeting performance requirements without having to resort to the use of an exotic or expensive base metal.
Electroplating uses an electric current to deposit a thin metal layer onto a surface. The process improves durability, appearance, and functionality. A substrate (cathode) and a metal source (anode) are immersed in an electrolyte solution. When current passes through the solution, metal ions from the anode bond to the cathode’s surface.
Industries use electroplating for corrosion protection, enhanced wear resistance, electrical conductivity, and improved aesthetics. For example, automotive parts receive chrome plating, jewelry gets gold finishes, and electronics often have nickel or tin coatings.
Factors like electrolyte type, current density, and plating time influence electroplating quality. Aerospace, medical, and automotive sectors depend on it for critical components.
RoHS compliant means a product meets the standards set by the Restriction of Hazardous Substances Directive. This European Union directive restricts the use of specific hazardous materials in electrical and electronic equipment.
The directive focuses on substances such as lead, mercury, cadmium, hexavalent chromium, and certain flame retardants. Manufacturers must ensure their products meet these limits to protect human health and the environment.
An RoHS compliant business ensures safer products by reducing harmful materials. It also supports recycling efforts by limiting hazardous waste. Companies displaying RoHS certification demonstrate commitment to environmental sustainability and regulatory standards. View our Accreditations page for more details.
Chrome metal is the common name for chromium, a hard, silvery-white element with the chemical symbol Cr. In industrial and everyday use, “chrome” typically refers to a thin layer of chromium electroplated onto a part to enhance its surface properties.
There are several types of chrome plating:
- Hard chrome for durability and wear protection
- Decorative chrome for aesthetic applications
- Thin Dense Chrome (TDC®) — Armoloy’s proprietary version, engineered for precision, uniformity, and long-lasting performance
Plating and coating are both methods used to cover the surface of a material to enhance its properties, and the terms are often used interchangeably. However, they differ in their application and composition:
- Plating: This involves depositing a layer of metal onto a substrate using electrochemical or chemical processes. Examples include thin dense chrome plating, gold plating, and nickel plating. Plating is primarily used for improving corrosion resistance, wear resistance, and aesthetic appeal.
- Coating: This can include a broader range of materials and techniques, such as paint, powder coating, or polymer coatings. Coatings can be applied by spraying, dipping, or brushing, and are used for protection against corrosion, improving appearance, and providing thermal or electrical insulation.
The minimum thickness of hard chrome plating typically starts at 0.0002 inches (5 micrometers) but can range up to 0.0005 inches (12.7 micrometers) depending on the application. For more demanding industrial uses, such as those involving high wear and corrosion resistance, the thickness can be greater, ranging from 0.0008 to 0.005 inches (20 to 127 micrometers)
Thin Dense Chrome (TDC), sometimes referred to as flash chrome or functional chrome, is an electroplated coating applied to manufacturing applications at a general thickness range of 0.0001” to 0.0002”. Unlike hard chrome, Armoloy Thin Dense Chrome is free of micro cracks which reduces the amount of contact with mating surfaces, significantly reducing friction and prolonging the life of machined components.
Armoloy Thin Dense Chrome (TDC®) achieves a surface hardness of 72 to 78 Rockwell C (Rc) — significantly higher than standard hard chrome, which typically falls between 68 and 72 Rc. This exceptional hardness is due to TDC’s dense, microcrack-free structure, which enhances wear resistance and surface integrity.
Because TDC is applied in extremely thin layers (typically 0.0001"–0.0005"), direct hardness measurements on coated components reflect a combination of the coating and the base material. To accurately measure coating hardness, TDC must be applied to a specially prepared metal coupon and tested using microhardness methods such as ASTM E384 (Vickers test).
This high surface hardness, paired with low friction and corrosion resistance, makes Armoloy ideal for precision tooling, bearings, valves, and linear motion systems operating under extreme wear conditions.
Decorative chrome is primarily used for appearance and corrosion resistance. It’s a multilayer coating, typically consisting of copper, nickel, and a very thin layer of chrome (under 0.00001"), applied to give surfaces a bright, reflective finish — common in automotive trim or bathroom fixtures.
Hard chrome (also called industrial chrome) is a functional coating applied at thicknesses over 0.002", sometimes exceeding 0.010" for wear protection. It has a microcracked surface, which can help with oil retention but may reduce corrosion resistance in some environments.
Thin Dense Chrome (TDC), such as Armoloy TDC, is a refined form of hard chrome applied at much thinner tolerances: typically 0.0001" to 0.0005". It features a micronodular structure instead of microcracks, offering better lubricity, wear resistance, and tolerance control. Because of its thinness, TDC can often be applied to precision components without affecting fit or dimensional integrity.
Components coated with Armoloy TDC are 100% safe for workers and end users. Plated components are used extensively in the food and drug industry, and routinely certified for REACH and RoHS compliance. In addition, Armoloy invests heavily in the newest technology to help ensure the safety of our employees and communities. For more information, learn about the misconceptions of chromium coatings.
XADC is a co-deposit of spherical nanodiamonds and Armoloy Thin Dense Chrome. XADC is useful for many applications and particularly excels as a coating for injection molds where high glass fiber resins are used, or in rotating components where especially low friction is desirable.
Thin Dense Chrome (TDC) can be applied to most ferrous and non-ferrous alloys. Thin Dense Chrome is not recommended for aluminum, magnesium, and titanium substrates without an intermediate layer. However, Armoloy’s Bi-Protec® and ALCOAT® are exceptional alternative coating technologies for plating on aluminum substrates and offer unparalleled performance in wear and corrosion protection in the most unforgiving environments.
Armoloy TDC has been successfully used in virtually all industries including aviation, automotive, nuclear power, oil and gas production, injection molding, food and drug manufacturing, and many others. Any component that could benefit from improved wear resistance, corrosion protection, or reduced friction and improved release properties will benefit from the use of Armoloy Thin Dense Chrome.
Yes, both Armoloy Thin Dense Chrome (TDC) and XADC are electrically conductive coatings. They form a metallic chromium layer that allows current flow across coated surfaces, making them suitable for grounding, EMI shielding, and static dissipation in certain applications.
However, conductivity may vary depending on coating thickness, surface condition, and substrate material. For applications requiring high or low electrical resistance — such as insulative barriers or controlled conductivity — it’s important to consult an Armoloy engineer to select the appropriate coating system or consider non-conductive alternatives.
Are Armoloy TDC Coatings Magnetic?
No, Armoloy Thin Dense Chrome (TDC) coatings are non-magnetic.
This characteristic is especially important in industries where magnetic interference could cause performance issues or safety concerns. Non-magnetic coatings like Armoloy TDC are ideal for:
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Medical Devices: In surgical environments and MRI applications, magnetic materials can interfere with sensitive imaging equipment or pose risks during procedures. Non-magnetic surfaces ensure compatibility with diagnostic tools and reduce the chance of distortion in imaging results.
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Electronics and Semiconductors: Precision instruments and high-frequency devices often require non-magnetic components to avoid electromagnetic interference (EMI), which can degrade signal quality or disrupt functionality.
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Aerospace and Defense: In these industries, non-magnetic materials help prevent navigational and communication disturbances, especially in environments where radar or sensitive magnetic sensors are involved.
In contrast, magnetic coatings may be suitable for industrial applications where magnetic properties are beneficial—for instance, in magnetic clamps, lifting equipment, or sensing mechanisms that rely on ferromagnetic interaction.
Armoloy TDC’s non-magnetic nature, combined with its exceptional wear resistance, corrosion protection, and hardness, makes it a trusted solution for components where both mechanical durability and magnetic neutrality are essential.
While Armoloy coatings can be applied to complex geometries, some extreme shapes may require special considerations or alternative coating methods to ensure complete coverage.
If not done correctly, chrome plating can lead to issues like poor adhesion, uneven coating, or premature wear. Armoloy’s advanced plating processes and quality control measures help prevent these common problems:
- Poor Adhesion – Some chrome coatings flake or peel due to improper surface prep. Armoloy ensures strong adhesion by using precision cleaning and pre-treatment techniques.
- Uneven Coating – Traditional chrome plating can result in inconsistent thickness. Armoloy’s Thin Dense Chrome (TDC®) provides a uniform, precision coating even on complex parts.
- Premature Wear & Corrosion – Standard chrome plating may not hold up under extreme conditions. Armoloy coatings enhance durability, wear resistance, and corrosion protection.
- Hydrogen Embrittlement – A risk in many plating processes, Armoloy minimizes this issue through specialized treatments to maintain material integrity.
Yes, both Armoloy Thin Dense Chrome (TDC) and XADC are electrically conductive coatings. They form a metallic chromium layer that allows current flow across coated surfaces, making them suitable for grounding, EMI shielding, and static dissipation in certain applications.
However, conductivity may vary depending on coating thickness, surface condition, and substrate material. For applications requiring high or low electrical resistance — such as insulative barriers or controlled conductivity — it’s important to consult an Armoloy engineer to select the appropriate coating system or consider non-conductive alternatives.
Diamond chrome plating is an advanced electroplating process that combines traditional chrome plating with the incorporation of nano-sized synthetic diamond particles. This proprietary technique creates a micronodular, crack-free surface texture that enhances the hardness, wear resistance, and thermal conductivity of the plated surface. The resulting coating is highly durable and capable of withstanding extreme wear conditions, making it ideal for applications in industries such as aerospace, automotive, and plastic injection molding.
Nano diamond coating is a process where a thin layer of diamond particles, typically at the nanometer scale, is applied to a material to enhance its properties. Diamond coating is achieved through methods like electroplating or chemical vapor deposition (CVD). Benefits of diamond coating include:
- Enhanced Hardness: Significantly increases surface hardness and wear resistance.
- Low Friction: Reduces friction, improving the efficiency and lifespan of components.
- Thermal Conductivity: Offers high thermal conductivity for better heat dissipation.
- Corrosion Resistance: Provides excellent protection against corrosion.
- Surface Uniformity: Results in a smooth, uniform surface with tight dimensional tolerances.
Chrome plating can be relatively expensive due to the complexity of the process and the cost of the materials involved. The price depends on several factors, including the thickness of the chrome layer, the size and shape of the object being plated, and any additional treatments required. However, investing in any form of protective coating can have a positive return on investment for metal assets. For example, the improved performance and protection achieved by chrome plating can prolong the service life of a component anywhere from 2 to 10 times its expected service life without a protective coating applied.
Factors Influencing Chrome Plating Costs
Several variables impact chromium plating costs, including the complexity of the process, material preparation, and quality requirements. Below are the primary factors that determine pricing:Size and Complexity of the Item
Larger or intricately designed parts require more labor, plating time, and materials, increasing costs. Simple, flat surfaces are easier to coat evenly, whereas complex shapes with recesses or deep grooves require more precision and process adjustments to achieve uniform coverage.Type of Chrome Plating
- Decorative Chrome Plating: This thinner layer of chromium is applied over a base of nickel or copper for aesthetic appeal and moderate corrosion resistance. It is generally less expensive due to the lower material cost and shorter processing time.
- Hard Chrome Plating: This process, used in industrial applications, involves depositing a much thicker chromium layer (often 0.0008 to 0.005 inches thick) to enhance durability, wear resistance, and friction reduction. The precision required for hard chrome plating makes it a more costly option.
- Thin Dense Chrome Plating – This advanced plating process provides extreme wear resistance, low friction, and high precision without buildup. It is ideal for applications requiring tight tolerances and is often more cost-effective in the long run due to its durability and performance benefits.
Surface Preparation
Before plating, parts must be meticulously prepared. This may include:- Cleaning and Degreasing: Essential for removing contaminants that could interfere with adhesion.
- Polishing or Grinding: Some applications require a mirror-like finish, necessitating additional polishing and buffing.
- Stripping Old Coatings: If a part already has chrome plating or another coating, it must be removed using an acid bath or abrasive techniques, adding to labor and processing costs.
Get a Custom Quote for Your Chrome Plating Project
Whether you're working on a new project or re-plating an existing part, our team can help you determine the best solution. Need a fast, accurate estimate? Unsure which coating is right for your application? Request a Custom Quote TodayCoating Cost Calculator
To estimate the chromium plating cost for your specific project, use our Coating CalculatorChrome Plating vs. Alternative Coatings
While chrome plating is a premium solution for durability and aesthetics, other coatings may offer cost-effective alternatives depending on the application:| Coating Type | Cost Range | Benefits | Considerations |
| Thin Dense Chrome (TDC) | Moderate | High wear resistance, corrosion protection, maintains tight tolerances | Decorative varieties are typically more expensive |
| Hybrid Coatings (TDC + Other Materials) | Moderate to High | Combines the benefits of multiple coatings for enhanced performance | Cost varies depending on the combination of materials used |
| Nickel Plating | Lower to Moderate | Good corrosion resistance, smooth finish | Some varieties may be less wear-resistant than chrome and require additional coatings for durability |
| Electroless Nickel Plating | Moderate to High | Uniform coating, excellent corrosion resistance, no need for electrical current | Higher cost than standard nickel plating; may require additional finishing steps |
Cost-Benefit Analysis of Chrome Plating
While chrome plating may have a higher initial cost than other coatings, its long-term performance benefits often outweigh the upfront investment. Here’s how:- Longevity & Extended Service Life
- Chrome plating can extend the lifespan of components by 2 to 10 times, reducing the frequency of part replacement.
- Its exceptional wear resistance is ideal for high-friction applications like industrial machinery, aerospace components, and tooling.
- Performance Enhancement & Cost Savings
- Reduces friction and galling, improving moving parts' energy efficiency and operational performance.
- Protects against chemical exposure in harsh environments, extending part longevity in medical, oil & gas, and aerospace industries.
- Precision & Reduced Rework Costs
- Thin Dense Chrome (TDC) coatings maintain tight tolerances, eliminating the need for costly post-plating machining.
- Compared to thicker coatings like hard chrome plating, TDC reduces dimensional distortion and the risk of uneven deposits.
- Aesthetic & Functional Benefits
- In applications where surface finish matters, chrome plating offers a low-friction, uniform surface that enhances both function and appearance.
- In high-precision industries, coatings that reduce micro-roughness can improve performance in bearings, molds, and medical devices.
- Total Lifecycle Value vs. Upfront Cost
- While chrome plating may have a higher initial chromium plating cost, its durability and performance benefits lead to a lower total cost of ownership over time.
- Ideal for industries where component failure is expensive (e.g., aerospace, automotive, and industrial machinery.
Alternatives to Chrome Plating
While Thin Dense Chrome (TDC®) is a premier solution for wear resistance and corrosion protection, certain applications may benefit from alternative or hybrid coatings. Below are Armoloy coating options that serve as viable alternatives to traditional chrome plating:Hybrid Coatings (Bi-Protec®)
- Composition: Combines high-phosphorus electroless nickel with an overlay of Thin Dense Chrome (TDC®) or XADC® for enhanced performance.
- Benefits: Offers corrosion resistance, wear protection, and chemical resistance, making it ideal for harsh environments.
- Applications: Used in oil & gas, aerospace, and medical industries where multi-layer protection is essential.
Electrolytic Nickel
- Composition: A direct current plating process that provides a thick, uniform nickel layer.
- Benefits:
- Excellent corrosion resistance in harsh environments.
- Can be polished to a bright finish or applied in a matte form.
- Strong adhesion to steel, brass, aluminum, and other substrates.
- Applications: Suitable for automotive, aerospace, and industrial tooling applications requiring a balance of durability and aesthetics.
Electroless Nickel Plating
- Types:
- Mid-Phosphorus Electroless Nickel: Provides a balance of hardness and corrosion resistance.
- High-Phosphorus Electroless Nickel: Offers corrosion resistance, especially in acidic and chemical-heavy environments.
- Benefits:
- Applies evenly on complex geometries, avoiding buildup on edges.
- Ideal for precision components needing tight tolerances.
- Excellent for marine, aerospace, and chemical processing industries.
Nickel-Teflon (Nyflon®)
- Composition: A co-deposit of electroless nickel and PTFE (Teflon®) for enhanced lubricity.
- Benefits:
- Low-friction, self-lubricating surface reduces wear and sticking.
- Provides moderate corrosion resistance with added smoothness.
- Ideal for components requiring both wear resistance and non-stick properties.
- Applications: Used in bearings, gears, and sliding mechanisms where lubrication is critical.
Molybdenum Disulfide (MoS₂) Coating
- Composition: A dry lubricant coating that reduces friction and enhances wear resistance.
- Benefits:
- Provides exceptional lubricity under extreme pressure and temperature conditions.
- Reduces galling, seizing, and fretting wear on moving parts.
- Suitable for vacuum and low-humidity environments where liquid lubricants fail.
- Applications: Commonly used in aerospace, military, and precision manufacturing where friction reduction is critical.
Xylan® Coating
- Composition: A fluoropolymer-based coating that provides low-friction and high corrosion resistance.
- Benefits:
- Non-stick, corrosion-resistant, and chemical-resistant properties.
- Can withstand extreme temperatures and harsh conditions.
- Excellent abrasion resistance, making it ideal for high-wear applications.
- Applications: Used in marine, automotive, oil & gas, and industrial applications requiring protection against chemicals and wear.
How to Obtain an Accurate Quote
When requesting a quote for chrome plating or alternative coatings, detailed information helps get accurate pricing and faster turnaround times. Here’s what to include:-
Provide Detailed Information About the Part
- Dimensions: Specify length, width, height, and weight to determine material usage and process time.
- Material Type: Identify the base material (steel, aluminum, brass, etc.), as some substrates may require additional pre-treatment.
- Existing Surface Conditions: Note whether the part is new, previously plated, or requires stripping and repair.
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Specify the Intended Application
- Wear Resistance: A harder, low-friction coating may be recommended for components exposed to abrasion or friction.
- Corrosion Protection: If the part will be in marine, chemical, or high-humidity environments, a hybrid or electroless nickel coating might be a better fit.
- Precision Requirements: If tight tolerances are required, TDC® or electroless nickel plating may be the most suitable choice.
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Define Quality and Performance Requirements
- Finish Quality:
- Industrial Finish: Focuses on functionality and protection.
- Precision Finish: Requires specific surface roughness and tolerances.
- Thickness Requirements: Specify if a standard or customized thickness is needed.
- Regulatory or Industry Standards: Mention any necessary compliance with ISO, ASTM, aerospace, or medical standards.
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Request Turnaround Time & Production Details
- Lead Time Expectations: Standard plating times vary based on complexity; expedited services may be available.
- Batch vs. Single-Part Orders: Volume orders can impact pricing, so indicate whether you need a single part or bulk processing.
Is Chrome Plating the Best Choice for Your Application?
Selecting the right coating depends on your industry's demands, environmental exposure, and performance requirements. While Thin Dense Chrome (TDC®) and hybrid coatings provide exceptional wear resistance, other coatings may better suit applications requiring specialized corrosion protection, low-friction surfaces, or chemical resistance. Key Factors to Consider: Durability & Wear Resistance – Ideal for high-friction components in aerospace, automotive, and industrial tooling. Corrosion Protection – Essential for marine, medical, and oil & gas environments exposed to harsh conditions. Precision & Tolerances – Thin Dense Chrome (TDC®) maintains tight tolerances without excessive buildup. Friction Reduction – Nickel-Teflon (Nyflon®) and Molybdenum Disulfide offer excellent lubrication for moving parts.Get Expert Guidance for Your Coating Needs
Not sure which coating is best for your application? Contact us today for a consultation or to request a customized quote.
Plastic deformation is the permanent distortion that occurs when a material experiences stresses. Plastic deformation allows the material to change shape when the applied stress exceeds the yield strength.
Bare metal surfaces can exhibit moderate to high friction, especially in metal-on-metal contact without lubrication. Friction levels depend on several factors:
- Surface Finish: Rough surfaces increase friction; polished or coated surfaces reduce it.
- Lubrication: Oils and greases lower friction significantly; low-friction coatings like Armoloy Thin Dense Chrome (TDC) reduce it even further.
- Material Pairing: Metal-on-metal contact generally has higher friction than metal-on-polymer or ceramic.
- Environmental Conditions: Heat, moisture, and contaminants can all raise or lower friction.
Yes, uncoated steel surfaces typically exhibit moderate to high friction, especially in steel-on-steel contact without lubrication. The friction coefficient can range from 0.5 to 0.8 in dry conditions — which may cause wear, heat buildup, or galling in dynamic assemblies.
Steel’s frictional behavior depends on several factors:
Surface Finish: Polished steel has lower friction than rough or untreated surfaces.
Lubrication: Oils, greases, or solid lubricants can significantly reduce friction.
Material Pairing: Steel-on-plastic or ceramic often generates less friction than steel-on-steel.
Environmental Conditions: Humidity, heat, and contaminants can increase or decrease friction.
In high-performance applications like automotive parts, machinery, and linear motion systems, friction can be effectively managed through surface coatings such as Armoloy Thin Dense Chrome (TDC), which reduces metal-on-metal drag and improves component longevity.
Galvanic corrosion occurs when two dissimilar metals are electrically connected in the presence of an electrolyte, causing one metal (the anode) to corrode faster. To fix or prevent it, engineers use the following mitigation strategies:
- Material Pairing: Choose metals close together on the galvanic series to minimize potential differences.
- Electrical Insulation: Use non-conductive gaskets, bushings, or washers (e.g., nylon, rubber, plastic) to isolate metals and prevent direct electrical contact.
- Protective Coatings: Apply barrier coatings like paints, powder coatings, or Armoloy TDC to prevent electrolyte access and reduce galvanic interaction.
- Cathodic Protection: Install sacrificial anodes (e.g., zinc or magnesium) to divert corrosion away from critical metals — commonly used in marine and pipeline systems.
- Environmental Control: Minimize exposure to electrolytes by reducing moisture, using sealants, or applying corrosion inhibitors.
- Design Improvements: Avoid crevices, ensure drainage, and design assemblies to limit electrolyte accumulation and electrical continuity.
- Regular Maintenance: Conduct inspections to identify early signs of corrosion and reapply protective measures as needed.
Pitting corrosion is a localized form of corrosion that creates small but deep cavities in metal surfaces, often due to chloride exposure, stagnant fluids, or material defects. Effective solutions involve both repair techniques and preventive strategies:
Repairing Pitting Corrosion:
- Mechanically remove pits via grinding, polishing, or blasting to eliminate affected material.
- Fill or resurface deeper pits with welding or metal-filled epoxies when structural integrity is compromised.
- Reapply protective coatings such as chromium, nickel, epoxies, or paints to restore corrosion protection.
Preventing Future Pitting:
- Use corrosion-resistant alloys with high PREN values, such as 316 or duplex stainless steels, instead of lower-grade 304 stainless.
- Design components to eliminate crevices, promote drainage, and reduce fluid stagnation.
- Apply barrier coatings or corrosion inhibitors in high-risk environments (marine, food processing, chemical washdowns).
- Schedule regular inspections and flush out salt or chemical residues to reduce localized attack.
Erosion corrosion is a type of material degradation caused by the combined effects of mechanical wear and chemical attack — typically from high-velocity fluid flow. To identify it accurately, engineers use a combination of visual inspection, non-destructive testing (NDT), and environmental analysis:
Visual Indicators
- Surface grooving, scalloped patterns, or flow-aligned streaks
- Localized thinning near elbows, valves, or impingement zones
- Increased surface roughness or material loss downstream of turbulent flow
Non-Destructive Testing (NDT)
- Ultrasonic Thickness Testing (UT): Detects metal loss and wall thinning
- Eddy Current Testing: Reveals near-surface pitting and cracking
- Radiography: Identifies sub-surface erosion in complex geometries
Environmental & Root-Cause Analysis
- Fluid chemistry testing for chlorides, acids, or abrasive particles
- Flow modeling to locate high-velocity or turbulent regions
- Microscopic examination to confirm combined mechanical/chemical wear mechanisms
Chemical resistance refers to a material’s ability to maintain its structural and functional integrity when exposed to corrosive chemicals, solvents, or aggressive environments. This resistance is determined by a combination of material composition, structural properties, and surface engineering:
- Material Composition: The inherent makeup of a material — such as alloying elements in stainless steel or resin types in polymers — defines how it responds to specific acids, bases, or solvents.
- Surface Coatings: Protective layers like Armoloy Thin Dense Chrome (TDC), ceramic coatings, or epoxies form physical and chemical barriers that block corrosive agents from reaching the base metal.
- Cross-Linking in Polymers: Thermoset plastics and elastomers with high cross-link density resist molecular breakdown by creating stable, tightly bonded structures.
- Barrier Properties: Some materials act as diffusion barriers, slowing or preventing chemical penetration. Thin dense chrome, for example, offers low porosity and high chemical inertness, ideal for corrosive industrial or food-grade environments.
Molybdenum disulfide (MoS₂) is applied as a solid lubricant coating using several techniques, depending on the substrate, operating environment, and desired performance. Common application methods include:
- Burnishing: Rubbing MoS₂ powder directly into the surface, typically for dry, low-load applications.
- Spray Coating: Applying MoS₂ in a binder or solvent-based suspension that dries into a uniform dry film layer.
- Chemical Vapor Deposition (CVD): A high-temperature process that deposits crystalline MoS₂ onto the surface, creating a durable, thin film for demanding environments.
Coatings reduce friction in bearings by creating a low-friction, wear-resistant surface that minimizes direct metal-to-metal contact. For example, Armoloy Thin Dense Chrome (TDC) features a micronodular surface structure that can retain trace lubricants or function effectively in dry or low-lube conditions.
This reduces frictional drag, prevents galling, and minimizes heat buildup during operation — all of which contribute to smoother performance and longer service life. In high-load or high-speed applications, coatings also protect against abrasion, fretting, and lubricant breakdown, improving bearing efficiency and reliability.
Aerospace coatings protect critical metal components from oxidation, moisture, fuel exposure, and salt spray corrosion by forming a thin, protective barrier over the substrate. Common aerospace coatings include electroless nickel, Armoloy Thin Dense Chrome (TDC), and anodized aluminum finishes.
These coatings are engineered to resist harsh environments — such as altitude condensation, de-icing chemicals, and jet fuel vapors — without degrading or flaking. For example, Armoloy TDC creates a hard, corrosion-resistant surface that adheres tightly to steel or titanium parts, making it ideal for use in landing gear, actuators, and aerospace fasteners.
By minimizing surface oxidation and chemical attack, these coatings extend component life and maintain the mechanical integrity required for aerospace safety and reliability.
Our highly experienced staff can support all aspects of the product lifecycle including the design, validation, manufacturing, and volume production phases.
Application engineers can assist with product design by helping to select the best coating for each application, ensuring that base metal selection provides the best combination of cost, performance, and manufacturability, and that critical design features can be reliably coated. In addition, we work with engineering partners that can provide:
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- Finite element analysis
- Thermal analysis
- Computational fluid dynamics
Yes, many single-use medical devices are coated — especially when performance, sterilization resistance, or biocompatibility is required. Common coatings include biocompatible chromium (like Armoloy ME-92), PTFE, and Parylene, depending on the device's function.
Coatings are used to reduce friction, improve cleanability, or prevent corrosion on tools such as catheters, guidewires, or surgical blades. However, not all disposable devices are coated; cost, sterilization method, and regulatory approval influence this decision.
For example, ME-92 is often applied to reusable surgical tools, but may also be used on high-performance single-use components that require ISO 10993 biocompatibility.
Yes, corrosion-resistant coatings such as Armoloy Thin Dense Chrome (TDC) and electroless nickel are commonly used to protect linear motion components — including ball screws, linear guides, and actuator rails — from exposure to moisture, chemicals, and industrial washdowns.
These coatings create a hard, non-porous barrier that prevents rust and pitting, extending the life of components in demanding environments. This is especially critical in food processing, pharmaceutical packaging, and outdoor automation systems, where unprotected steel surfaces would otherwise degrade quickly.
Yes, Armoloy ME-92® and BIO-TDC coatings provide an excellent surface for laser marking and are widely used in medical device manufacturing where traceability and UDI compliance are required. These biocompatible coatings support high-contrast, permanent markings without compromising the coating’s integrity or performance.
The microcrystalline surface of ME-92 and the nodular structure of BIO-TDC both respond well to laser energy, producing clear, readable marks — even on complex geometries like clamps, forceps, or orthopedic screws. This makes them ideal for instrument serialization, branding, and regulatory identification in surgical and clinical settings.
No, high-performance coatings such as Armoloy Thin Dense Chrome (TDC) are applied in extremely thin layers — typically between 0.0001" and 0.0005" per surface — allowing coated parts to maintain tight dimensional tolerances. This makes TDC an excellent choice for linear motion components such as precision bearings, guide rails, and ball screws, where fit, alignment, and repeatable motion are critical.
Because of its low effective thickness and uniform deposition, TDC can often be applied to existing part designs without modification, avoiding rework or redesign of mating components. This dimensional consistency, combined with its wear and corrosion resistance, makes TDC ideal for automation, robotics, and high-performance motion assemblies.
Yes, Armoloy provides chrome plating services through a global network of Process Fulfillment Centers located across North America, Europe, Asia, and Africa. Whether you're based in the U.S., Europe, or overseas, Armoloy can service your region with consistent access to its proprietary Thin Dense Chrome (TDC) and XADC coatings.
These fulfillment centers specialize in fast-turnaround plating for a range of industries — including aerospace, food processing, medical devices, and nuclear components. To find the nearest Armoloy facility or arrange shipping logistics, visit our location directory or contact our central support team.
Yes, we are happy to work with suppliers to choose the right coating, develop a robust process, and identify the ideal processing partner to fit any application. Learn more about our process on our How It Works page.
PFAS (Per- and Polyfluoroalkyl Substances) are a group of synthetic chemicals widely used in various industrial and consumer products for their water-resistant, grease-resistant, and heat-resistant properties. Often referred to as "forever chemicals," PFAS do not break down easily in the environment or the human body, leading to potential long-term health and ecological concerns.
Where Are PFAS Found?
PFAS can be found in:
- Non-stick cookware
- Water-repellent fabrics
- Food packaging
- Firefighting foams
- Industrial processes, including chrome plating for mist suppression
Why Are PFAS a Concern?
PFAS have been linked to:
- Environmental contamination of water, soil, and air
- Accumulation in humans and wildlife
- Potential health risks, including hormonal disruptions, immune system effects, and certain cancers
A classic example of cavitation occurs in ship propellers.
When a ship's propeller spins at high speeds, it can create areas of low pressure in the water. In these low-pressure zones, water vaporizes, forming tiny bubbles. As the bubbles travel into areas of higher pressure, they collapse or implode, releasing a significant amount of energy. This implosion can cause pitting and erosion on the propeller surface, reducing its efficiency and potentially leading to damage over time.
Cavitation can also happen in pumps, turbines, and other fluid-moving machinery, where similar pressure changes cause bubble formation and collapse.
Abrasive wear is primarily caused by the presence of hard particles or rough surfaces that slide or roll across a softer material. Here are the main factors contributing to abrasive wear:
- Hard Particles: Particles such as dust, sand, or debris in the environment can become trapped between surfaces and cause abrasion. These particles act like cutting tools, removing material from the softer surface.
- Surface Roughness: Rough or uneven surfaces with protrusions can abrade softer materials during contact. Smoother surfaces reduce the likelihood of abrasive wear.
- Contact Pressure: Higher contact pressures increase the abrasive action between surfaces. Maintaining optimal pressure levels can help minimize wear.
- Material Hardness: The hardness difference between contacting materials significantly affects abrasive wear. Softer materials are more susceptible to abrasion by harder counterparts.
- Environment: Harsh environments with high levels of particulate matter, such as mining or construction sites, are prone to abrasive wear. Proper sealing and protective measures can reduce exposure to these conditions.
- Lubrication: Inadequate or improper lubrication can lead to increased friction and abrasion. Using the right type of lubricant and ensuring regular maintenance can help mitigate this issue.
An example of dealloying is the dezincification of brass. Dezincification occurs when brass, an alloy of copper and zinc, is exposed to corrosive environments, leading to the selective removal of zinc. This leaves behind a porous, weakened structure of copper, which can compromise the integrity and mechanical strength of the brass component. Dezincification often occurs in plumbing systems, where brass fittings are exposed to water containing chlorides or other aggressive chemicals.
An example of erosive wear can be found in the blades of a gas turbine engine. In gas turbine engines, high-velocity particles such as sand or dust suspended in the air intake can strike the turbine blades at high speeds. This repeated impact of particles leads to the gradual removal of material from the blade surfaces, resulting in surface pitting, thinning, and eventually, a reduction in the blade's aerodynamic efficiency and structural integrity.
Preventive Measures:
- Air Filtration: Installing advanced air filtration systems to remove particles before they enter the engine.
- Coatings: Applying wear-resistant coatings to the turbine blades to enhance their durability.
- Regular Maintenance: Conducting regular inspections and maintenance to identify early signs of wear and address them promptly.
An example of fretting can be observed in the connection between an aircraft's wing and fuselage. In this application, slight oscillatory movements occur between the mating surfaces due to aerodynamic forces during flight. This micro-motion leads to repeated contact and friction, causing the removal of material from the surfaces in contact. The resulting damage, known as fretting wear, manifests as pitting, grooving, and the formation of oxide debris, which can weaken the structural integrity of the connection.
Preventive Measures:
- Use of Lubricants: Applying appropriate lubricants to reduce friction and wear.
- Surface Treatments: Employing surface coatings or treatments to increase hardness and resistance to fretting.
- Design Modifications: Improving joint design to minimize relative motion and increase contact stability.
An example of surface erosion is the damage observed on the leading edges of helicopter rotor blades. During flight, helicopter blades are subjected to high-speed impacts from rain, sand, and other airborne particles. These impacts erode the blade surface, leading to material loss, pitting, and roughness, which can compromise the aerodynamic efficiency and structural integrity of the blades.
Preventive Measures:
- Protective Coatings: Applying erosion-resistant coatings to the rotor blades to enhance their durability against particle impacts.
- Design Modifications: Incorporating design features that reduce the impact angle and velocity of particles on critical surfaces.
- Regular Inspections: Conducting routine inspections and maintenance to detect early signs of erosion and repair damaged areas promptly.
Industrial coatings are specialized surface treatments applied to materials like metals, concrete, and plastics to protect them from corrosion, wear, and environmental damage. These coatings are essential for enhancing the durability and performance of various industrial products and infrastructure. Types of industrial coatings include epoxy, polyurethane, acrylic, polysiloxane, and zinc-rich coatings, each serving different protective and functional purposes such as resistance to chemicals, abrasion, and extreme temperatures.
Corrosive wear is caused by the interplay of chemical and mechanical factors. Here are the primary causes:
- Chemical Agents: Exposure to corrosive substances such as acids, alkalis, salts, and oxidizing agents can initiate chemical reactions on the material surface. These reactions degrade the material, making it more susceptible to wear.
- Mechanical Stress: Mechanical actions like abrasion, erosion, or friction accelerate the removal of the chemically weakened surface layer. This exposes fresh material to further chemical attack, perpetuating the cycle of wear.
- Environmental Conditions: Harsh environments, including high humidity, temperature extremes, and the presence of corrosive gases, can exacerbate corrosive wear. For example, marine environments with saltwater are particularly aggressive.
- Material Properties: Materials with low corrosion resistance or poor mechanical strength are more prone to corrosive wear. The selection of appropriate materials is crucial to prevent rapid degradation.
- Contaminants: The presence of contaminants, such as dirt or abrasive particles, can enhance both corrosion and mechanical wear. These particles can embed in surfaces and act as sites for corrosive attack.
- Electrochemical Factors: In some cases, electrochemical reactions, such as galvanic corrosion, can occur when two dissimilar metals are in contact in the presence of an electrolyte. This can lead to accelerated corrosive wear.
Gauge corner cracking (GCC) refers to the formation of cracks at the gauge corner, which is the outer edge of the railhead where the wheel flange contacts the rail. This type of cracking is a significant issue in railway systems and can lead to rail failure if not properly managed.
Causes of Gauge Corner Cracking:
- High Contact Stresses: The interaction between the wheel and rail generates high contact stresses at the gauge corner, leading to material fatigue and crack initiation.
- Rolling Contact Fatigue: Repetitive rolling contact under high loads causes micro-cracks to form and propagate in the rail material.
- Friction and Slip: The relative motion between the wheel and rail, especially during curves or braking, induces additional shear stresses and contributes to crack growth.
- Material Properties: Rail steel composition and microstructure play a critical role in susceptibility to GCC. Harder rail materials may resist wear but can be more prone to cracking under cyclic loading.
- Environmental Factors: Temperature variations, moisture, and contamination can exacerbate the development and propagation of cracks.
- Regular Inspections: Conducting frequent inspections using non-destructive testing methods, such as ultrasonic or eddy current testing, to detect early signs of GCC.
- Rail Grinding: Periodic rail grinding to remove surface defects and maintain optimal rail profile, reducing stress concentrations.
- Lubrication: Applying rail lubricants or friction modifiers to minimize friction and wear at the gauge corner.
- Material Improvements: Utilizing advanced rail steels with improved resistance to fatigue and cracking.
Good chemical resistance means that a material can endure prolonged exposure to a variety of chemicals without significant deterioration or loss of properties. Characteristics of good chemical resistance include:
- Durability: The material remains physically and chemically stable over time when exposed to chemicals.
- Minimal Swelling or Degradation: The material does not absorb chemicals or swell excessively, which can lead to loss of mechanical integrity.
- Retention of Mechanical Properties: The material retains its strength, flexibility, and other mechanical properties after chemical exposure.
- Low Permeability: The material does not allow chemicals to pass through easily, maintaining a barrier to protect underlying surfaces or structures.
Mold release coatings are essential for preventing materials like plastics, rubber, or composites from sticking to molds during the manufacturing process. These coatings improve the efficiency of mold operations, reduce material buildup, and extend the lifespan of molds. There are several types of mold coatings, each offering unique benefits for specific applications.
- Plating and Coating: Electroplating or chemical processes create a protective metal coating, such as thin dense chrome or electroless nickel, on the mold. These coatings are primarily chosen for corrosion and wear resistance.
- Chemical Vapor Deposition (CVD): CVD coatings, such as silicon carbide or boron nitride, are chemically reactive layers that enhance the mold's hardness and resistance to wear and heat.
- Physical Vapor Deposition (PVD): PVD forms a thin film on the mold using materials like TiN or TiCN. These coatings increase hardness and protect the mold from wear and abrasion.
- Oxidation Treatment: This method creates an oxide layer on the mold surface to increase corrosion resistance and surface hardness. Common techniques include anodizing and phosphating.
- Thermal Spray: This technique uses a spray gun to apply melted metal or alloy materials, such as ceramics, carbide, or metals. It forms a hard, wear-resistant layer that improves mold durability.
- Polymers: Polymer coatings like polyether or polyurethane are applied to molds to provide excellent wear and corrosion resistance.
In engines, molybdenum disulfide is primarily used as an additive in lubricants and greases to reduce friction and wear. It is particularly effective in protecting engine parts under extreme pressure and temperature conditions. MoS2 is commonly used in two-stroke engines, such as those in motorcycles, as well as in components like CV and universal joints. Its ability to maintain lubrication even when oil levels are low makes it invaluable in ensuring the longevity and performance of engine parts.
Overheating in welding occurs when the metal is exposed to excessively high temperatures during the welding process, causing issues such as reduced strength, grain growth, oxidation, and distortion. It can lead to weakened weld joints, warping, and poor mechanical properties, making the weld susceptible to failure. Controlling heat input is crucial to prevent overheating and ensure weld quality.
Adhesion is a complex phenomenon explained by several theories. Here are the four main theories of adhesion:
- Mechanical Interlocking Theory: This theory posits that adhesion occurs when the adhesive penetrates the pores and irregularities of the substrate, creating a mechanical bond. This interlocking effect enhances the adhesive strength by anchoring the adhesive to the surface.
- Electrostatic Theory: According to this theory, adhesion results from electrostatic forces between the adhesive and the substrate. When two surfaces come into contact, an electrical double layer forms, generating electrostatic attraction that contributes to the adhesive bond.
- Diffusion Theory: This theory suggests that adhesion is due to the interdiffusion of molecules at the interface of the adhesive and the substrate. When materials with similar molecular structures come into contact, their molecules intermix, creating a strong adhesive bond through molecular entanglement.
- Chemical Bonding Theory: This theory states that adhesion is caused by the formation of chemical bonds (such as covalent, ionic, or hydrogen bonds) between the adhesive and the substrate. These bonds result from chemical reactions at the interface, providing strong adhesion.
Adhesive wear can lead to several types of failures, significantly impacting the performance and longevity of mechanical components. Here are the common failures associated with adhesive wear:
- Galling: This occurs when severe adhesive wear causes the surfaces to seize and weld together. It results in significant material transfer and surface damage, leading to operational failure.
- Scoring: Visible grooves or scratches appear on the surface due to repeated adhesive contact. This type of failure can reduce the efficiency of sliding components and increase friction.
- Seizing: The surfaces lock together due to strong adhesive forces, often leading to a sudden and complete failure of the component. This can halt machinery operations and cause extensive damage.
- Material Transfer: Particles from one surface transfer to another, leading to uneven wear and potential imbalance in rotating machinery. This can cause vibrations and reduced precision in operations.
- Surface Fatigue: Repeated adhesive contact can lead to surface fatigue, characterized by the initiation and growth of cracks. Over time, this results in the spalling or flaking of material.
- Pitting: Small pits or craters form on the surface due to localized adhesive failure. This can compromise the structural integrity of components and lead to premature failure.
Examples of fluoropolymers include:
- PTFE (Polytetrafluoroethylene): Known widely as Teflon®, used in non-stick cookware and industrial applications.
- FEP (Fluorinated Ethylene Propylene): Used in wire insulation and chemical processing equipment.
- PFA (Perfluoroalkoxy Alkane): Known for its high temperature and chemical resistance, used in semiconductor manufacturing.
- ETFE (Ethylene Tetrafluoroethylene): Used in architectural applications for its durability and resistance to weathering.
- PVDF (Polyvinylidene Fluoride): Used in the chemical industry for its resistance to solvents and acids.
Stress corrosion cracking (SCC) is a complex phenomenon that requires three key factors to occur simultaneously:
- Tensile Stress: The presence of tensile stress, either applied or residual, is essential for SCC. This stress can result from mechanical loads, thermal cycles, or welding processes.
- Corrosive Environment: A specific corrosive environment is necessary to initiate and propagate SCC. Common environments include chlorides for stainless steels, caustic solutions for carbon steels, and ammonia for brass.
- Susceptible Material: The material must be susceptible to SCC in the given environment. Factors such as alloy composition, microstructure, and heat treatment can influence susceptibility.
- Stress Relief: Reduce residual stresses through heat treatment, annealing, or stress-relief processes.
- Environmental Control: Minimize exposure to specific corrosive agents known to cause SCC for the material in use.
- Material Selection: Use materials with higher resistance to SCC in the intended service environment.
Fretting is caused by small, repetitive oscillatory motions between two contacting surfaces under load. Several factors contribute to the occurrence of fretting:
- Relative Motion: Micro-movements or vibrations between contact surfaces, typically in the range of micrometers to millimeters, lead to repeated contact and separation.
- High Contact Pressure: Increased contact pressure intensifies the frictional forces and wear between the surfaces.
- Environmental Conditions: Presence of oxygen and humidity can exacerbate fretting by forming abrasive oxide particles (fretting corrosion).
- Material Properties: Softer materials are more susceptible to fretting wear, and the presence of hard particles can act as abrasives.
- Surface Roughness: Rough surfaces increase the likelihood of asperity interactions, leading to higher wear rates.
- Cyclic Loading: Components subjected to cyclic or oscillatory loads, such as vibrations or thermal cycling, are more prone to fretting.
- Bolted Joints: Slight movements in bolted joints due to dynamic loading.
- Bearings: Micro-movements between bearing surfaces under load.
- Electrical Contacts: Vibrations in electrical connectors leading to fretting corrosion.
Certain Xylan coatings are FDA approved for non-stick applications like cookware, bakeware, and food processing equipment. When properly applied and used as intended, Xylan non-stick surfaces are safe for food contact and can withstand typical cooking temperatures up to approximately 500°F (260°C), depending on the specific formulation.
As with any non-stick surface, damage to the coating can affect its performance and safety. Scratches or deep abrasions may expose the underlying material and reduce non-stick effectiveness. Using non-metal utensils and avoiding overheating helps preserve the coating’s integrity.
Xylan coatings are engineered to remain stable under recommended temperatures and do not release harmful chemicals when used correctly. However, extreme overheating or damage may compromise the coating and lead to potential degradation.
Not all Xylan formulations are food-grade. Many industrial-grade Xylan coatings are designed for corrosion protection, wear resistance, and industrial equipment where food contact is not involved. Always verify that the specific Xylan product meets food safety standards, such as FDA compliance, before selecting it for non-stick cookware or food processing equipment.
Stress corrosion cracking can occur across a wide range of temperatures depending on the metal type and chemical exposure. SCC happens when tensile stress, a corrosive environment, and temperature conditions align to weaken the material.
Typical SCC temperature ranges by material:
- Stainless steel (in chlorides): Most susceptible between 50°C and 150°C (122°F–302°F), especially in marine or humid industrial environments.
- Carbon steel (in caustics): SCC often starts above 60°C (140°F), particularly in strong alkaline conditions.
- Brass (in ammonia): Cracking can occur at room temperature, commonly known as season cracking.
- High-strength alloys: Certain aluminum or titanium alloys may crack across a broader range depending on the environment and load.
In the Production Part Approval Process (PPAP), the five submission levels define how much documentation a supplier must provide to verify part quality and process consistency. Each level reflects the depth of review required by the customer:
- Level 1: Part Submission Warrant (PSW) only
- Level 2: PSW plus limited supporting data and product samples
- Level 3: PSW with complete supporting documentation and product samples (most common level)
- Level 4: PSW and additional requirements defined by the customer
- Level 5: Full documentation and samples with an on-site review at the production facility
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