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This work inspects the metallurgical and tensile demeanor of pulsed current gas tungsten arc welded ERNiCrCoMo-1 filler wire on alloy 80A weldment. Defect free weldment was achieved in a four pass through PCGTA welding. The center of the weld microstructure is decorated with equiaxed dendritic structure and columnar dendritic structure. SEM analysis showed the existence of Mo, Fe and Ti secondary phase precipitation in the grain boundary region of the weld zone. Tensile testing was conducted to analysis the strength and ductility of weldment. The result showed that the tensile strength and ductility were lower than that of base metal (BM).

The current research work scrutinized the influence of plasma arc in the metallurgical and mechanical behavior of Nimonic 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 at the weld interface region columnar dendritic structure was observed. Metallurgical analysis showed the Cr and Ti secondary precipitates in the interdendritic region of the WZ. The existence of M23C6 and Cr2Ti were observed through the X-ray diffraction analysis. Both tensile test and microhardness test were conducted to study the mechanical properties of weldment. The result concluded that both the strength and ductility inferior than base metal and the hardness of the weld bead is similar to that of BMl.

The present paper mainly focuses on the analysis and multi-factor optimization of cutting process parameters in turning Hastelloy C-276 using an integrated approach of Weighted Aggregated Sum Product Assessment (WASPAS) and criteria importance through inter-criteria correlation (CRITIC). To achieve this objective, a design of experiment (DoE) is employed for the three control parameters: cutting speed, feed rate, and cutting depth. The insert used for turning is a coated carbide insert (PVD: Ti-Al-N). Different responses are recorded: force, tool wear, and surface roughness in machining attributes, chip structure, chip thickness, chip thickness ration, shear angle, and friction coefficient in chip-tool interface indices. Uncertainty probabilistic study depends on Monte Carlo (MC) method applied.

The current work investigates the hot corrosion demeanour of Hastelloy X weldment produced with autogenous mode through key-hole plasma arc welding (K-PAW). The hot corrosion test has been performed for weldment in molten salt-1 (MS-1) (75 % Na2SO4 + 25 % V2O5) and molten salt-2 (MS-2) (75 % Na2SO4 + 20 % V2O5 + 5 % NaCl) circumstance for 25 hrs (25 cycles) at 900 °C. The MS-1 substrate of both base metal and weldment provided the lowest weight gain than the MS-2 substrate. The NaCl in the MS-2 causes severe hot corrosion on the substrate, whereas the absence of NaCl in MS-1 reduces the hot corrosion effects. The highest parabolic constant is observed for K-PAW weldment in MS-2 condition. The tendency of hot corrosion rate follows the order of, Base Metal MS-1 < K-PAW MS-1 < Base Metal MS-2 < K-PAW MS-2. The occurrence of protective phases like chromium oxides (Cr2O3), spinel oxides (NiCr2O4 and NiFe2O4) Nickel oxide (NiO) on the substrate resist the further oxidation.