Gas tungsten arc welding of as-cast AlCoCrFeNi2.1 eutectic high entropy alloy

The AlCoCrFeNi2.1 eutectic high entropy alloy is of great interest due to its unique mechanical properties combining both strength and plasticity. Here, gas tungsten arc welding was performed for the first time on an as-cast alloy. microstructural evolution welded joints assessed by electron microscopy with backscatter diffraction, synchrotron X-ray diffraction analysis thermodynamic calculations. Microhardness mapping tensile testing coupled digital image correlation were used investigate distribution across joint. base material, heat affected zone fusion are composed FCC + B2 BCC structure, although relative volume fractions vary joint owing weld thermal cycle. nanoprecipitates that existed in material started dissolve into matrix closer boundary. Compared evidenced grain refinement higher cooling rate experienced during solidification. This translates increased hardness this region. exhibit good strength/ductility balance failure occurring material. work establishes potential using arc-based joining alloys.