Studies on Metallurgical and Mechanical Properties of Plasma Arc Welded Aerospace 80A Grade Alloy 2020-28-0466
The current research work scrutinized the influence of plasma arc in the metallurgical and mechanical behavior of alloy 80A weldment. Defect-free weld bead of 6 mm thickness was achieved in a single pass through plasma arc welding. The microstructure of weldment is decorated with cellular dendritic structure at the center and columnar dendritic structure at the weld interface region. Scanning electron microscopy (SEM)/ Energy-dispersive X-ray spectroscopy (EDS) analysis showed the Cr and Ti secondary precipitates in the interdendritic region of the weldment. The presence of M23C6 and TiC were observed through the X-ray diffraction analysis. Both tensile test and microhardness test were conducted to study the mechanical properties of the weldment. The result concluded that both the strength and the hardness of the weld bead is slightly lower than the base metal.