INFLUENCE OF LASER PROCESSING ON THE MICROSTRUCTURE, MICROHARDNESS AND CORROSION RESISTANCE OF DIFFUSION BORONIZED LAYER PRODUCED ON 145Cr6 TOOL STEEl

Abstract

The paper presents the results of laser processing of diffusion boronized layer on 145Cr6 tool steel. The aim of the study was to investigate the microstructure, phase composition analysis, microhardness as well as corrosion resistance of the newly-formed layer. Boronized layer was produced at 950 ° C by 6 h in mixture consisted of boron carbide B 4 C as a source of boron, kaolin as a filler and ammonium chloride as activator. Laser processing were conducted using 3 kW diode laser. As a result of influence the laser beam on the boronized layers the presence of three areas was observed: remelted zone, heat affected zone and substrate. The boronized layers after laser processing were characterized by high microhardness and good corrosion resistance. The zone enrich in boron was a 2-3 times thicker than diffusion boronized layer.