Study on Microstructure and Properties of the Additive Layer of FCW Wire for H13 Steel

Abstract

In order to provide research data on direct forming and rapid recovery of metal parts by arc fuse additive manufacturing technology. In this paper, the flux cored wire prepared from H13 die steel strip was used as the wire material, and the arc additive manufacturing process was used to carry out multi-channel and multi-layer surfacing welding process test on the Cr12MoV steel substrate, and the quality, structure and performance of the additive layer were studied. The results show that there is obvious fusion line between layers, and there is no porosity, crack or unfusion in the section. The average interlayer microhardness was 325HV, slightly higher than that of annealed substrate. The change pattern of microstructure from bottom to top layer is from equiaxed crystal to larger equiaxed crystal. The top layer is columnar crystal, and the microstructure is mixed structure of martensite, alloy compound and bainite. The tensile test showed that the tensile strength between layers was about 700Mpa, with no obvious yield strength and the elongation reaching 11.9%.The wear test shows that the additive layer has better wear resistance, and wear is a mixture mechanism of abrasive wear and adhesive wear. H13 steel flux-cored wire is suitable for direct manufacture of wear - resistant parts and mold repair.