Surface Treatment
The world’s first amorphous chrome plating Chroamor is a chromium-based alloy plating containing 2% to 4% carbon that provides both ultra-high rigidity and excellent wear resistance.
Characteristics of Chroamor
Film structure
The film of Chroamor has an amorphous structure. This means that Chroamor has different properties from normal chrome plating with a crystal structure.
Heating Chroamor at 200 to 600℃ increases its hardness up to Hv1800. This hardness is about twice as high as normal hard chrome plating.
Heat resistance
With an amorphous structure, Chroamor can maintain a high level of hardness even at 600°C. Compared to hard chrome plating, with which the hardness drops drastically at 400°C, its heat resistance is extremely good.
Changes in the hardness of normal chrome plating and Chroamor during heat treatment
Changes of hardness at different temperatures during heat treatment time
Wear resistance
Oxide films on the surfaces of Chroamor provide better wear resistance than other surface treatments.
Changes of hardness at different temperatures during heat treatment time

Relationship between heat treatment
and the amount of wear

Differences in coefficient of kinetic friction between hard chrome plating and Chroamor

Corrosion resistance
Chroamor films with a thickness of up to approximately 5 μm are free of cracks, pinholes, and other defects, thereby providing excellent corrosion resistance.

Cross section of
Chroamor film

Cross section of
hard chrome plating film

Chemical resistance
Chroamor has three to six times higher corrosion resistance to hydrochloric acid than normal chrome plating.
Plating characteristics

Chroamor allows low-temperature treatment compared to diffusion treatments such as carburizing, nitriding, and boride methods, or dry surface hardening methods based on chemical or physical vapor deposition, which means that Chroamor imposes less thermal influence on materials.

Chroamor can be detached and replated in the same way as normal chrome plating.

Chroamor is a high-hardness plating, thus causing macrocracks to occur when the plating thickness exceeds 5 μm. However, thanks to the excellent characteristics described above, Chroamor provides sufficient functionality even if its thickness is a fraction of the thickness of normal chrome plating.

Materials that can be plated
Chroamor can be applied to a wide range of metal materials including steel, stainless steel, copper, and copper alloys.
Uses of Chroamor
Chroamor has hardness nearly twice as high as chrome plating as well as various excellent mechanical properties, providing a wide range of uses including applications that cannot use normal chrome plating due to its durability and thin film treatment on precision components that must maintain their shape.
Practical uses
Semiconductor-related parts

Various sealing molds, various pins (such as ejector pins, movable pins, pilot pins, guide pins, and core pins), various punches (such as bending punches, forming punches, hole punches, and cutting punches), various dies (such as bending dies and forming dies), various plates (such as guide plates, feed plates, and heater plates), various blocks (such as center blocks, cull blocks, heater blocks, and guide blocks), cavities, plungers, etc.

Parts for molding resin T-shaped dies, clasps, screws, collars, adjusting rings, lips, pipes, mandrels, nipples, nozzles, sleeves, various molds, adapters, plates, guides, etc.
Parts for molding glass Annealing screws, guides, forming rollers, pushers, chutes, various molds, etc.
Spinning machine parts Clasps, various guides, reed blades, perforated sheets, hot rollers, guides, rollers, etc.
Wear-resistant parts Cams, shafts, rolls, guides, blades, pulleys, pistons, various pins, plates, etc.
Machined metal parts Bending dies, drawing dies, forming rolls, punches,guides, dies, rollers, etc.
Other various corrosion-resistant parts, heat-resistant parts, printing machine parts, food manufacturing related parts, precision parts, parts molded by die casting, pharmaceutical manufacturing related parts, logistics machinery parts, etc.
Semiconductor-related parts
Chroamor is widely used for semiconductor-related parts (such as sealing molds and ejector pins) in order to enhance mold releasability and wear resistance, prevent galling, and improve solder adhesiveness. There are some cases where thin chrome plating is used for surface treatment of semiconductor-related machine parts. However, semiconductor chips have become shorter, smaller and thinner, their manufacturing process has become faster, and filler has been used as additives, and these changes have caused problems such as poor mold releasability, galling on pin surfaces, and solder adhesion problems with molded terminal parts. Using Chroamor for such parts can improve these problems.
Molded resin parts
Chroamor has been used for a large number of molded parts made of highly corrosive and adhesive resins such as phenolic resins, vinyl resins, cellulose acetate, and amino resins. There are many cases where these parts are generally subject to normal chrome plating from the viewpoint of mold releasability and wear resistance, but durability under harsher conditions is expected due to various reasons, including development of new materials such as engineering plastics, use of various additives such as calcium carbonate and glass fiber, and increased molding temperature. For such applications, Chroamor is effective in improving resin releasability and fluidity and preventing the adhesion of resin, thereby helping to improve the quality of plated products and extending the service lives of various components.
Molded glass parts

Glass forming molds are often heated at high temperature (600 to 700℃) and so if normal chrome plating is applied, it cannot be used for a long period due to problems such as the occurrence of hairline cracks, the peel-off and transfer of oxide films formed on the surfaces, and their resultant abrasion. However, using Chroamor forms fine and rigid oxide films through heat treatment, making the peel-off of oxide films extremely little and retaining their rigidity at high temperature, making it possible to extend the service life of the product and reduce the maintenance burden.

Spinning machine parts
Chroamor is also used for spinning machine parts such as clasps. New fiber aimed at high functionality has been used and machine operating speeds have been increased for cost reduction, causing the abrasion circumstances of spinning machine parts to become harsher than before. If Chroamor is used for components that produce significant wear on normal chrome plating, their service lives can be extended.
Wear-resistant parts

Most metal powder, ceramic powder, and other powder used with powder injection molding are very hard materials, causing significant wear on molded parts and affecting the working environment due to dust produced by abrasion. Applying Chroamor to die plates has been producing satisfactory results. For example, a die plate had severe wear with a maximum depth of 0.7 mm when approximately 700,000 shots were delivered, but the same die plate to which Chroamor was applied had almost no wear even after 3,000,000 shots were delivered.

Corrosion-resistant parts
Chroamor has better corrosion resistance to chlorides, sulfides, and artificial perspiration and better erosion resistance than normal chrome plating. This means that Chroamor can be used to prevent corrosion on components subject to significant corrosion and abrasion, fuel-system machine parts, and copper alloys.
Comparison of functional plating films
  Otec’s functional plating film Reference plating film
Type CHROAMOR Chrome plating TFE-LOK Electroless nickel plating
Plating method Electroplating Electroplating Chrome plating Chemical treatment Mechanical treatment Electroless plating
Film structure Cr-C
amorphous material
crystalline material
composite film
amorphous material
Thickness uniformity
Corrosion resistance
Wear resistance
Heat resistance
(Heat treatment temperature)
As deposited Around Hv1,000 Around Hv900 Around
Around Hv500
400℃ Around Hv1,700 Around Hv850 - Around Hv950
600℃ Around Hv1,800 Around Hv600 - Around Hv650
Self-lubricating capabilities As deposited:○
600°C heat treatment:◎
Non-adhesiveness As deposited:△
600°C heat treatment:○
(◎: Excellent, ○: Good, △: OK)
Application examples
Pins Screw
Maximum applicable size for Chroamor
Anything that can be put in a plating bath with internal dimensions of 400 mm × 400 mm × 3,000 mm. (For details, please consult with Otec.)