Microstructure evolution and mechanical properties in a gas tungsten arc welded Fe42Mn28Co10Cr15Si5 metastable high entropy alloy

Weldability studies on high entropy alloys are still relatively scarce, delaying the deployment of these materials into real-life applications. Thus, there is an urgent need for in-depth weldability novel advanced engineering alloys. In current work, as-cast Fe42Mn28Co10Cr15Si5 metastable alloy was welded first time using gas tungsten arc welding. The weld thermal cycle effect microstructure evolution over joint examined electron microscopy in combination with backscatter diffraction, synchrotron X-ray diffraction analysis, and thermodynamic calculations. Furthermore, tensile testing hardness mapping were correlated evolution. across unveiled, including origin ε-h.c.p. phase at different locations material. Different strengthening effects measured throughout associated resulting microstructure. A synergistic smaller grain size fusion zone, overturns reduced volume fraction this phase, increasing local strength Moreover, brittle nanosized σ also found to play a critical role joints’ premature failure during mechanical testing.