Mechanical Properties of the Recycled Hard Metals Utilized by the Grinded Wastes

WC-Co type hard metals used as die materials are mainly machined by grinding. The wastes produced by grinding, which are very fine grains ( < 10 mu m), are usually discarded. In this experiment, the recycling technique of grinded wastes is studied. The mechanical properties of recycled materials are examined by hardness testing (H sub R A) and transverse rupture strength testing. It is found that recycling of grinded wastes could be completed by seven processes. Especially, the reducing process at 1073K and the recarburizing process before compacting are very important. Recarburizing adds graphite of total 6.0 mass%. The mechanical properties of recycled materials almost satisfy JIS standard values (H5501).