Cast iron surface hardening - by inductive heating underneath sand or ceramics melt retaining shell

摘要

Hard surface layer is produced on a workpiece made of carbon-contg. cast iron, such as a camshaft, by melting it through inductive heating and letting it solidify to a carbide-contg. white iron layer with a ledeburite structure. Prior to heating, the surface is convered by a thin moulding layer of hardened sand or ceramics. Arrangement creates an inductive melting process of surface layers in which the liq. cast iron does not become displaced.