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Collet project

I am in the midst of designing a special collet chuck. In the design, there are two metal components that will be sliding past each other on a 13.5 degree inclined surface. There will exist a 77000 lb load between these two surfaces. I am interested in a plating process that will provide no more than 0.1 friction co-efficient. I can supply a drawing to help illustrate if required to clarify.

Regards,

Tim Winard
- Addison, Illinois USA
 

Tim,

Prior to the coefficient of friction I would consider adhesion properties and most of all the effects in the fatigue strength of your part. Remember that most plating processes produce some hydrogen embrittlement and other (basically those of hard metals) also produce internal stress in the plate itself that may lead to notch sensitivity. Your application seems more suited for a surface modification rather than a plating. There are numerous processes from the very simple nitriding to sophisticated PVD's that can be better candidates.

Good luck.

Guillermo Marrufo
Monterrey, NL, Mexico