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.
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.
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)
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.
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.
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.
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
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
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.
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.
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.
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.
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.
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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