Crack elimination by Aluminum concentration in GTAWcladedAlxCoCrFeNi (x=۰.۷ and ۱) high entropy alloy.

In this study, two high entropy alloys of AlCoCrFeNi (Al۱) and Al۰.۷CoCrFeNi (Al۰.۷), werecladded on plain carbon steel using the gas-tungsten arc welding process at a welding currentof ۱۸۰ A and a welding speed of ۱.۴ mm/s. Clads microstructures and types of cracks havebeen investigated by a combination of optical microscopy (OM), field emission scanningelectron microscopy (FESEM), X-ray diffractometry (XRD) analysis, and microhardnessmeasurements. Results indicate that the Al۱ clad has a petal-like structure of the BCC and Crrichphases. Both intergranular and transgranular cracks were identified in the Al۱ alloy. Thetype of cracks were assumed to be a solidification cracking. By reducing Al in the Al۰.۷ alloy,the Cr-rich phase was eliminated, and a new phase with the FCC crystal lattice formed invarious morphologies. A combination of factors, including a decrease in the solidificationrange, formation of the FCC phase, and reduction in hardness, were attributed to crackelimination in the Al۰.۷ alloy.