Influence of the Composition of Saturating Mixture on the Depth of Diffusion of Chromium and the Coating Structure During Chromovanadizing

Abstract

The results of metallographic and x-ray phase studies of 35Kh2N3 steel samples after two-component thermal diffusion saturation with chromium and vanadium in mixtures of different compositions are presented. It is shown that when metallic chromium is replaced by ferrochromium, the structure and the phase composition of the coating change; the amount of carbide and nitride phases decreases and the amount of the Cr – Fe – V solid solution increases. The use of serpentine in the saturating mixture (an emitter of oxygen anions, which creates a flow of charged particles directed to the saturated part) elevates the depth of diffusion of chromium into the metal from 20 to 50 μm. The hardness of the coatings due to chromizing in metallic chromium powder with ferrovanadium and in a mixture of ferrochromium with ferrovanadium amounts to 2000 HV and 1750 HV, respectively.