Compensation of filler wire deflection in robotic gas metal arc welding processes

This paper examines the issue of wire deflection in wire and arc additive manufacturing (WAAM) and robotic welding, which leads to process instability and defects in printed geometry. The study focuses on the deflection of alloy 625, alloy 718, and 3Si1 welding wires during the deposition process. Measurements were taken to determine the relationship between wire deflection and the amount of wire used. Regression models were developed for each material to predict initial wire deflection and changes in deflection due to contact tip wear. The results showed that the deflection of alloy 625 and alloy 718 wires followed a nonlinear pattern for the first 500 m of wire, while the deflection of 3Si1 wire followed a nearly linear trend. The intensity of the contact tip wear is dependent on the normal contact load, which decreases as the wear increases. A generalized regression model of wire deflection was constructed based on the obtained regressions and the study of the wire’s deformed state. Based on these models, an algorithm was developed to correct the wire deflection by adjusting the tool center point coordinates. The effectiveness of the developed algorithm was verified in practice.