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What is friction transformation hardening?


In friction transformation hardening, the material is friction heated by a rotating wheel held in contact with the surface to be treated. The surface can be flat or curved, and either the wheel can be traversed over the stationary component, or the component can be traversed whilst the wheel is kept in position.

The wheel travels at a surface velocity of around 60-80m/sec and is in contact with any given point on the component's surface for a very short period of time so that wear of the wheel is not significant.

For the process to work the material must, of course, be capable of air transformation hardening; suitable materials include medium carbon, high carbon and a range of low alloy steels. The process has been successfully adopted in Eastern Europe for improving the fatigue performance of rollers used in the production of shaped steel products. It has been investigated at TWI as a method of hardening rail steels.

Further information:

FAQ: What is friction surfacing?

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