Slag-Free Mechanism, Microstructure Evolution, and Wear Resistance of Self-Shielded Metal-Cored Wire A type of Fe-Cr-C-B-Mn iron-based, slag-free, self-shielded metal-cored wire was established

In this paper, a type of Fe-Cr-C-B-Mn self-shielded metal -cored wire was developed to fabricate experimental hardfacing alloys. The slag-free mechanism, microstructure evolution, and wear resistance were investigated. It was observed that the traces of slag detached from the metal droplet weld metal, and slag bridge at a high temperature and detached from the surface of the weld after solidification, contributing to a slag-free weld. The slag detachability at the high -temperature stage of the welding process was discussed. The 3D morphologies indicated that the blade-like and rod -like shapes of M-7(C, B)(3)-type carbides are, in fact just based on differences in sectioning. Moreover, gaps existed at the edge of all primary M-7(C, B)(3) carbides, and austenite and eutectic M-3(C, B) carbides may be formed in the gap of primary M-7(C, B)3 carbides. With the increase of load, the friction coefficient of hardfacing alloys decreased, but the wear loss increased gradually.