STRUCTURAL FEATURES OF VACUUM-DEPOSITED HIGH-HARDNESS CHROMIUM COATINGS

The structure and hardness of ion-plasma coatings, obtained by evapora ting chromium with a low-pressure compressed arc, from a melting cruci ble with and without clusterization of the vapor flow, was studied. It is shown that the Hall-Patch equation can be used to calculate the yi eld point of the coatings where the effective grain size corresponds t o the size of a dislocation cell. On the basis of the three temperatur e zones of coating applications, the structure of ion-plasma chromium coatings corresponds to the zone of heat application. High hardness of the coating is achieved primarily as a result of extremely small grai n size (down to 0.1 mum).