THE EFFECT OF DOPING WITH BORON AND TITANIUM ON THE PHASE COMPOSITION AND PROPERTIES OF CHROMIUM DEPOSITED METAL

Abstract

Article deals with the improvement of wear resistance of machine components which may be achieved by an adequate selection of abrasion resistant materials. Iron-based alloys with chromium, manganese, titanium, in combination with boron and carbon have been selected as hardfacing alloys due to their high hardness and wear resistance. Research studies shown the following main results. Hardfacing macrocracks take place on the surface of deposited layer (metal with no boron) and microcracks of various lengths located in the deposited metal as well as in a fusion zone. Addition of boron to the deposited metal results reduction of amount of microcracks. Qualitatively the effect of increasing boron concentration on the phase composition of deposited metal both groups is identical, as for alloys without titanium, or with it. The proportion of boroncontaining eutectic grows, and the martensitic-austenitic matrix decreases accordingly. Correlation between eutectic part and deposited metal hardness is shown.