EFFECT OF SHOCK SINTERING TEMPERATURE AND CARBON CONTENT OF THE WC–Cо HARDMETAL USED AS AN ANODE ON THE MASS TRANSFER IN ELECTROSPARK DEPOSITION

Abstract

The effect of shock sintering temperature and carbon content of the VK25 hardmetal and the processing time and discharge energy in the electrospark deposition of the hardmetal onto steel 45 samples on the mass transfer, thickness, and microhardness of the resultant surface layers is studied. The experiments were performed employing an Elitron-24 facility providing a discharge energy of 0.34–1.1 J. The VK25 hardmetal was produced by shock sintering in the range 1150–1300 °С using WC with different carbon contents. For the maximum mass transfer, the hardmetal sintering temperature has to be 100–150 ºС lower than the temperature at which samples with the highest strength were produced. The maximum mass transfer was observed when the hardmetal was depleted of carbon (3.9 instead of estimated 4.59 wt.%). A protective layer 100–200 µm thick, with a hardness of 8.0–13.7 GPa, was pro-duced on the steel samples.