Investigations of Microstructure and Phase Composition of Different Self-Shield Flux-Cored Wire Slag System

Abstract

A series of slag were fabricated by self-shield welding of different flux-cored wire. The microstructure and phase composition of those slag were investigated by means of metallographic microscope, SEM,EDX and X-ray diffraction respectively. The result demonstrated that the slag forming material of TiO2 and Al2O3 tenders to form the framework structure of slag, while CaO and MnO2 inclines to incorporate in the grain boundary. Furthermore, the dense and dendrite phase structure of slag was beneficial for the removal of slag. On the contrary the slag with tiny needle and skeleton-like structure was difficult to clear up. In conclusion, the detachability performance was not only affected by the microstructure, but also by the chemical composition of the slag system.