Hard surface finish for hammer head - has series of projecting irregular nodules formed by electroerosion or spark-discharge

摘要

The roughening and hardening surface-finishing process produces hard irregular projecting nodules (3) on an otherwise smooth and relatively soft metal surface. The process applies to the working surfaces of various tools, e.g. hammers or clamps. The resultant surface is more resistant to wear and less likely to skid or slip. The nodules may be of micro or macro-asperity form of varying configuration and distributed uniformly about the working surface. The implanting of the asperities may be effected by spark-discharge, by electro-erosion, or by electric arc, and the asperities may be harder than the receptive surface.