Aluminium Finishing
Midland Polishing & Plating Ltd offer a specialist aluminium finishing service.
Aluminium extrusions or castings can be electroplated in bright chrome or satin chrome.
They can also be finished in electrophoretic lacquer whether it be straight onto the base material or after satin nickel, bright nickel or brushed nickel.
We can offer hexavalent chrome or trivalent chrome.
The hexavalent chrome is suitable for a high corrosion resistance such as the automotive, marine, and brewery trade.
The trivalent chrome is preferable for decorative components that are not in a harsh environment.
The grade of aluminium has a bearing on the quality of the aluminium finishing.
Regarding the castings a low silicon content is advisable toobtain a better quality finish.
The electrophoretic lacquer process does not have the complexity of the nickel/ chrome but the casting still needs to be of a good quality to avoid pitting, porosity and cold flow marks.
Depending on the quality required the castings may require metal polishing to remove imperfections but some porosity is not always evident until after processing.
The aluminium extrusions are generally of a higher quality in comparison to castings and more suitable for electroplating but sometimes the lower the number in the series table the better.
It is generally advisable to provide samples of the material to be used for finishing trials to establish the operations required and the quality standard for approval.
The process to nickel plate aluminium is to etch the surface either in an alkali or acidic solution to provide a key and remove any smut or film.
The component is then coated with a zincate film, known as a conversion coating to allow the surface to be electroplated with copper or nickel.
For more information on Aluminium Finishing, electrophoretic lacquer and electroplating contact Midland Plating & Polishing on 01902 421174 or use the contact form.