Electron-beam welding of high-entropy alloy and stainless steel: microstructure and mechanical properties

An autogenously dissimilar Al0.1CoCrFeNi-high entropy alloy/stainless steel (i.e., AISI 304) weld joint was produced by an electron-beam welding technique. The weld metal followed mode A of solidification and resulted in a fully austenitic columnar dendritic microstructure due to rapid cooling and lower chromium equivalent to nickel equivalent (Creq/Nieq) ratio (1.12–1.14). Tensile test sample fractures at the base metal (Al0.1CoCrFeNi-high entropy alloy) and illustrates higher strength (the yield and ultimate strength of 310 ± 10 MPa and 560 ± 15 MPa, respectively) than that of Al0.1CoCrFeNi-high entropy alloy, ensuring the suitability of the electron-beam welding for the Al0.1CoCrFeNi-high entropy alloy/AISI 304 stainless steel joint structures designed with respect to Al0.1CoCrFeNi-HEA properties. The influence of the manufacturing process (electron beam welding) is highlighted in terms of microstructure and mechanical properties.