Process characteristics of V-shaped coupling dual GTA-based additive manufacturing

Abstract

The deposition efficiency of gas tungsten arc (GTA) additive manufacturing is quite low despite its superior quality in comparison with other arc-based manufacturing processes. Therefore, V-shaped coupling dual GTA-based additive manufacturing (VCG-AM) process was proposed in this study to solve the problem. Thin-wall part with sound formation was acquired by VCG-AM, with the deposition efficiency reaching more than twice of conventional single GTA-based additive manufacturing (SG-AM) process. The microstructure of mainly polygonal ferrite and pearlite was obtained via both processes, and the grain size of VCG-AM was slightly larger than that of SG-AM, related with the higher heat input. The pearlite assembled near the grain boundary of the polygonal ferrite, and a larger volume fraction of pearlite formed in the VCG-AM sample due to the lower cooling rate. The average microhardness of the VCG-AM sample was a little lower than that of the SG-AM sample, while the impact absorbing energy and ultimate tensile strength was close. Both VCG-AM and SG-AM part demonstrates ductile fracture based on the tensile fracture analysis.

Keywords

• V-shaped coupling dual GTA-based additive manufacturing
• Deposition efficiency
• Microstructure
• Mechanical properties