Analysis on the Microstructure and Mechanical Properties of Welding Joint of Low Alloy Structural Steel Plate by Narrow Gap MAG

摘要

The narrow gap automatic MAG welding equipment in this article is a narrow gap gas metal arc automatic welding system developed by Wuhan University, which has remarkable advantages of low heat input and high efficiency. The low heat input reduces the tendency of grain coarsening and other bad non-equilibrium structures in the weld microstructure, improving the mechanical properties of welding joints. Selecting the welding of low carbon low alloy structural steel-Q345B as the research object, this paper systematically analyses the microstructure and mechanical properties of Q345B welding joint by narrow gap automatic MAG welding process, it turns out that the weld joint obtains good mechanical properties in this way.