Hard chrome plating

What is hard chrome plating?

Hard chrome plating is the term given to the electroplating process where chromium is distributed from a chromic acid solution.

There are a variety of types of hard chrome which include porous chromium, micro-porous chromium, crack free chromium and micro-cracked chromium.

The micro-cracked coatings and porous coatings must acquire a minimum thickness between 80 and 120Âľm in order for them to confer adequate corrosion resistance. These platings are designed to retain lubricant which is used for sliding and bearing types of applications.

Chrome plating is the solution for resisting wear and corrosion along with its tribological (low friction) characteristics.

Please visit our website to view our hard chrome plating services and more!

What is Metal Polishing?

Metal Polishing - a method used to clean and restore plated and solid items. This is so that a shiny and smooth finish can be achieved. Metal polishing can be used on metals such as Chrome, aluminum, nickel, copper, silver and gold. There's many different tools which are used when polishing such as buffers & polishers, acids, solvents ad many more different types.

Metal polishing can create hazards including chemical exposure, entrapment/entanglement and ergonomics.

Types of Metal Polishing Aluminium and Stainless Polishing Aluminium and stainless both oxidize on the surface of the metal which helps protect the metal from corrosion, once this oxidization is removed and smoothed down it can have a brilliant finish just like a chrome shine.

Chrome Polishing Chrome is not polished but it is cleaned, as chrome doesn't oxidize much at all it is very hard and thin unlike stainless and aluminium. It's often found that once a chrome plate is scratched it's better to replace the part. However you can use solvents and soaps to clean the chrome with clean/soft rags.

Smoothing When metals are pitted and scratched it's best to smooth the metal before attempting to polish.

This can be done with wet dry paper or wet sand which is then soaked in water.

You must do this until all pits and scratches are gone in which case it'll be uniform, dull grey then it's ready to be buffed.

Buffing Buffing is the final stage of polishing metals, this is achieved with a rotating wheel which has buffing compound on, such compounds contain a mixture of wax and fine abrasives.

When buffing a lot of people tend to use emery and rouge which is goof for first cut on aluminium and stainless, it's common to go directly from wet sanding to this stage.

To see when a metal is finished buffing you'll have to feel, keeping the wheel moving until the metal looks completely polished with no scratches... it's best to wipe off the wax then to take a look before deciding.

Hard Chrome Plating & Decorative Chrome: What's the difference?

Have you ever wondered what’s the difference between decorative chrome or hard chrome plating?

Chromium is about the same hardness in both decorative chrome and hard chrome plating, about 800 to 1000 VHN (which is incredibly heavy). The main difference is found in the thickness of the deposit.

For the decorative purpose of chrome, it is seated best on nickel, which adheres incredibly well to copper – the combination of all three offers possibly the best corrosion protection resistance available. Decorative chrome thickness can vary from anywhere between a few hundredths of a mil to one mil. The mirror finish will effectively only be as good as the finish that is on the surface before the chrome, so it’s all a very difficult process at times.

An example of chrome plating For the purpose of being functional, or take either take advantage of the extremely low friction that chrome holds or for building surfaces and pistons, hard chrome will be plated with a thickness anywhere between 1 to 50 mills.

When used as a bearing surface, chrome simply must be micro-finished, something which will then provide a level of friction much lower than any other metal when used against the likes of steel, iron, brass, bronze or aluminium alloys. There’s something that you mustn’t do; Do not use chrome against chrome. Chrome is much harder than casehardened steel, so we are then left with a perfect set-up for longwearing working surfaces. Chrome will resist pretty much all organic and inorganic compounds and acids, except hydrochloric acid.

For more on hard chrome plating, surface finishing & polishing, please visit our website.