Steel Hardness vs. Wear Resistance

[kaiserman]

APPLICATION: A kingpin and 2 bushings are used on a semi-truck front axle and spindle combination.

Currently, we supply a kingpin that has a higher hardness than the bushing hardness - thus the bushing wears a certain amount for a certain amount of truck useage. By altering the hardnesses of both bushings and kingpins in the test lab the results thus far are less than banner. (No clear equations can easily be derived from the limited data to date).

QUESTION: Does a theoretical equation exist to determine the measured wear of a material based on its hardness? Being a mechanical engineer, I was hopeful to be pointed in a materials direction at least.

BASIC DESIRE: In an application if a kingpin has a hardness of say "X" and a bushing has a hardness of "Y" it will produce measured wear of say "n". Now if the hardness of the kingpin, bushing or both is altered - will the measured wear be altered by a known amount?

Thanks
kaiserman

Regards,
Tim Kaiser
VW Kaiser Engineering, Inc.

http://www.vwkaiser.com

 

[TVP]

The answer to both of your questions is no. Wear cannot be easily distilled into an equation due to the numerous effects: material microstructure, presence of coating/oxide/surface films, normal & shear stresses, friction/lubrication, sliding velocity, sliding length, etc. In general one can say that harder materials will wear less, but there are other effects that are equally important.

 

[unclesyd]

Here is a very good paper by Peter Min that elaborates further on the complexity of a wear problem as refered to in the post by TVP.

http://www.solorb.com/dat-heads/digests/V4.100/D100

 

[kaiserman]

Thanks so much to TVP and unclesyd - VERY HELPFUL! However, I must admit, I was hopeful the wear questions would pose simple explanations. Wow - I have much to learn in the "material wear world".

Eng-tips come through again. Questions go out - answers come in!

Thanks
Kaiserman

Regards,
Tim Kaiser
VW Kaiser Engineering, Inc.

http://www.vwkaiser.com

 

[unclesyd]

We appreciate your acknowledgement.

Not as a reward, but a site I believe you will find interesting when it come to wear.

http://www.tribology-abc.com/