Effect of Aluminum on Microstructure and Mechanical Properties of Weld Metal of Q960 Steel

• DOI: 10.3390/cryst12010026
• Publication Date: 2021-12-24T13:38:46Z
• Authors: Zongxuan Zou; Zhengjun Liu; Xingyu Ai; Dan Wu
• Keywords: Acicular ferrite; Tempering; Hardenability; Charpy impact test

High-strength low-alloy (HSLA) steel is used in important structural members because of its strength and plastic toughness. Q960 HSLA obtained by adding an appropriate amount alloy elements quenching tempering treatment on the basis ordinary low-carbon steel. This kind has strong hardenability due to added. Cold cracks, embrittlement softening heat-affected zone easily occur after welding. In particular, low-temperature impact toughness cannot meet requirements limits use. this paper, self-shielded welding adjust content aluminum flux-cored wire. The relationship between weld metal (WM) microstructure properties was studied tensile test test, influence mechanism Al analyzed. results show that when 0.21%, energy at 0 °C~−60 °C best, can reach 1035 MPA number pores small. size inclusions WM mostly less than 1.0 μm Al2O3 spherical oxide. It become center acicular ferrite (AF) increase nucleation probability. However, with content, large irregular AlN are produced, which reduces welded joint.