What is Hard Chrome Plating?
Hard chrome plating is an electroplating process in which a layer of chromium is applied to a surface to improve corrosion and wear resistance, reduce friction, and extend the life of parts used in extreme working environments. A wide range of materials, component sizes and complexity can be plated making hard chrome a popular choice for many industrial and commercial applications.
Hydraulic cylinder rods, bearing fits and seal areas frequently get damaged and worn from heavy use. When no longer functional, a part can be hard chrome plated and polished or ground back to OEM Spec. This process can be repeated multiple times reducing equipment downtime and substantial replacement costs.
Improved corrosion and wear resistance. Reduced friction.
Longer part life.
A Proven Process
Our hard chrome plating process involves submerging a work piece in an electro-chemical bath. An electric current draws chromium metal from the chromic acid solution and applies it to the substrate. The result is a completely adhered layer of chromium that will extend the life of parts and components.
Before chroming a workpiece, it is prepared for ideal chrome adherence. The work piece is cleaned thoroughly, inspected, existing chrome is removed and any damage repaired. The piece is then pre-polished to a consistent size then masked for full control of the chromed area. After plating, the workpiece is polished to a precise dimensional tolerance and desired surface finish.
Hard Chrome Plating and Polishing
Up to 46′ in length or 24″ in diameter
Suitable Materials for Hard Chrome Plating
Any ferrous and most non-ferrous metals can be hard chrome plated, except for magnesium and titanium which typically require an underlay of zinc, copper or nickel. Aluminum can be hard chrome plated, although some alloys require an undercoat of copper or nickel.
Common materials we plate are: Steel, cast iron, stainless steel, bronze, brass and copper.
Hard Chrome Plating Applications
- Hydraulic and pneumatic cylinder rods, stages and barrels
- Swivel posts and bodies
- Pump shafts, geared shafts and splined shafts
- Downhole tools
- Inside diameter bores
- And more…
Hard chrome can be applied in thickness of 0.0005” – 0.025” (0.012mm – 0.635mm)
Hard chrome is classified as a “cold” process where the operating temperature of 58 – 60 degrees Celsius ensures no damage to the physical or mechanical properties of the base material.
Benefits of Hard Chrome Plating
The success of hard chrome plating can be attributed to the many benefits and unique characteristics of the process. The increased hardness alone would not be sufficient to secure widespread use, as a number of hard materials and hardening processes are available. It is the combination of the improved qualities below that give hard chrome plating such remarkable results.
Electro-deposited chrome is extremely hard, typically 66-70 HRC. Through hard chrome plating, the surface hardness of your component is increased without modifying its properties.
Hard chrome has a very high resistance to atmospheric oxidation and a good resistance to most oxidizing and reducing agents (with the exception to Chlorides and other Halides).
Hard chrome has a very low coefficient of friction when compared to steel. This allows a component to operate at a lower temperature during operation, extending the life of your equipment.
Sacrificial Wear Layer
Since hard chrome deposits can be removed with chemical strippers, without destructive effect to base material, the part can be stripped and re-plated repeatedly when worn.
The high hardness and low frictional properties of hard chrome, provide excellent resistance to abrasion and mechanical contact.
Microcrack characteristics of hard chrome allows for oil retention which improves lubricity of plated parts.
Hard Chrome Plating FAQs
Hard chrome plating is a form of electroplating. It is popular for its use as a surface coating due to its hardness, ability to minimize sliding wear, corrosion protection and for extending the life of metal parts.
Electro-deposited chrome is extremely hard, typically 66-70 on the Rockwell “C” scale which is used to determine the indentation hardness of a material. In comparison, hardened knife steels typically measure 58-62 HRC.
Hard chrome has excellent corrosion resistance but it plates in a micro-crack structure so it will rust over extended periods of time in wet environments.
No. Although the processes are similar, they serve different functions. Hard chrome is widely used in industrial applications for increased wear and corrosion resistance, reduced friction, and lubricant retention. Decorative chrome is a much thinner layer of chromium used mainly for aesthetic appeal.
No, as the metal has been ionically dissolved in the electrochemical bath.
No, we are not set up for automotive parts, but there are many places around that can help.
Any ferrous and most non-ferrous metals can be chrome plated. The most common materials are steel, cast iron, stainless steel, bronze, brass, and copper. Metals like magnesium and titanium require an underlay of zinc, copper, or nickel. Aluminum typically requires a copper or nickel undercoat.
The life span of hard chrome plating depends on the working environment and how thick the chrome is applied.
Hard chrome can be applied anywhere from 0.0005” – 0.025” (0.013mm – 0.635mm). The max chrome thickness is generally dictated by clearance to mating parts.
A piece can be hard chrome plated many times as long as the base metal remains in good condition.