Microstructure and Fracture Performance of Wire Arc Additively Manufactured Inconel 625 Alloy by Hot-Wire GTAW

Abstract

In this work, an Inconel 625 thin-wall structure was fabricated by the gas tungsten arc welding (GTAW) hot-wire arc additive manufacturing process. The microstructure and mechanical properties of the Inconel 625 samples, extracted from different orientations and locations of the thin-wall structure, were investigated and compared. The results showed that the additively manufactured Inconel 625 component, made by hot-wire GTAW, had good quality. Its microstructure consisted of dendrites, equiaxial crystals, and cellular crystals. The average hardness from the bottom to the top was similar, indicating that the thin wall had good consistency. The plasticity in the deposition direction was better than those in the other three regions, which was related to the dendritic structure in the sedimentary direction.

A review on microstructure and mechanical properties of Inconel 625 alloy fabricated using wire arc additive manufacturing process

“…The mechanical properties of the WAAMfabricated alloy were compared with other process produced alloys where heat treatment increased the yield strength and decreased the elongation but no significance change in tensile strength and aging heat treatment decreased the mechanical properties (Marchese et al, 2020). The four different samples were taken top, middle, bottom, transverse direction and compared as shown in Figure 6, that the tensile strength of top and bottom reported close while the better elongation is reported in transverse direction sample (Wang et al, 2022). The optical microstructure of the Inconel 625 fabricated using WAAM process reveals the columnar dendritic structures of the cross-section (Y-Z plane) to the build direction that was perpendicular to the deposition direction and also the interface between the layers as shown in Figure 7.…”

“…Impact strength found using Charpy impact test which fall within the range from 160 to 200 J, while the fracture toughness found using crack tip opening displacement test which was within the range from 0.49 to 1.05 mm (Akselsen et al , 2022). The investigation of fracture performance of wire arc additively manufactured Inconel 625 alloy by hot-wire GTAW, tensile samples were extracted from the bottom, middle and top areas of the wall component, and the result shows that yield and tensile strength were smaller related to dendritic structure while the hardness of the samples indicates good consistency and the elongation rate in the deposition direction was better while tensile properties of the horizontal direction were opposite to the results of the elongation rate (Wang et al , 2022). The study of mechanical properties for Inconel 625 using wire arc additively manufactured thin wall components which was deposited on a low-carbon alloy steel substrate, the specimens were etched with 9 ml hydrochloric acid and 3 ml nitric acid, the tensile test was conducted at room temperature with a 3 mm/min strain rate, the specimen was annealed for 30 min, 1 h and 2 h, the result shows that 2 h annealed sample has the highest UTS and 30 mins annealed sample shows the highest YS, with increase in annealing temperature the laves phases are decreased which improves the UTS (Tanvir et al , 2019).…”

Light Alloys and Their Applications

“…Subsequently, a self-consistent thermodynamic database was obtained based on experimental data, and its establishment provided a basis for the further development of the Mg-Zn-Sm alloy. Wang et al [11] prepared Inconel 625 alloy thin-walled structures using the gas tungsten arc welding (GTAW) hot-wire arc additive manufacturing process and studied the microstructure and mechanical properties of the Inconel 625 samples extracted from different orientations and locations of the thin-wall structure. The results showed that the additively manufactured Inconel 625 component, made via hot-wire GTAW, was of good quality.…”