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Wear coating for aluminium to aluminium sliding contact

Q. We are developing a new heat engine that has a cast aluminium crosshead slider that bears against a flat running surface on a cast aluminium housing. Peak sliding speed is only 2m/s, pressure of the order of 5MPa. Plenty of lubricating oil will be present. We require a coating for these surfaces that will give good wear properties. I have heard of a silicon treatment for aluminium bores in internal combustion engines -used in some Mercedes models and Porsches 944 and 928. I cannot find any information on it however. Can anyone help with suggestions of suitable coatings/treatments?

Paul van de Loo
- Adelaide, SA Australia
2000

A. Hello,

I am an engineer for materials science.

We are able to produce surface-layers on aluminium alloys with a thickness of some millimeters and with a hardness up to 300 HV - under certain conditions even more. We use the electron beam welding and high alloyed filler material to get a wear resistant surface.

Best regards

Dr. Wolfgang Schwarz
Institute of Solid State and Materials Research - Dresden, Germany
2001

A. Hi, Paul

The coating on the Mercedes and Porsche cylinders is probably nickel-silicon carbide plating -- silicon particles occluded into nickel plating.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
April 1, 2011