Study on Fillet Weld Model of Micro-Plasma Surfacing for Aero-Engine Blade

During the repair of aero-engine blade, the damaged part was firstly cut off, then multi-layer and multi-pass welding was carried out in the new plane. At the weld corner area especially corner point, due to improper welding process, too many droplets enter the weld pool to increase the weld height and width, which causes weld bulge and affects the welding quality. According to the weld characteristics of the corner zone of the blade during micro-plasma arc welding, the weld model of the corner zone was established.Firstly, a single pass welding seam model was established by Parabola curve fitting method, and the model was proved to be able to describe the profile of single pass welding seam accurately. Then, a weld forming model of double-weld fillet overlapping was proposed. The experiment shows that the model can greatly reduce the bulge of the fillet weld, and it can meet the requirements of the repairing precision of the aero-engine blade.