Work Hardening

Work hardening of materials is a condition to be avoided.

Work hardening is caused by the heat generated by the cutting tool transferring to the work piece material causing plastic deformation. In fact, it is appears to act like a heat treatment to the work piece but on a lower scale. To recognize this condition the part being machined will have a very shiny glazed surface and appear slippery. The hardness in the machined part can even realize the same hardness of the cutting tool.

This condition is often the result of a cutter rubbing against the workpiece instead of actually cutting the workpiece material. This can be caused by dull cutters, too slow a feedrate, or other conditions.

The following steps should be taken to overcome this condition:

Once again, proper tool maintenance will help to reduce work hardening problems.