CoCuFeNi high entropy alloy reinforced by in-situ W particles

(CoCuFeNi)_100-xW_x (x = 0, 5, 15) high entropy alloys (HEAs) were prepared by arc melting. Five atomic percent of tungsten can completely dissolve into CoCuFeNi, forming face-centered cubic solid solution. In-situ W particles formed in CoCuFeNi matrix with 15 at.% W addition with semi-coherent interface between W particles and CoCuFeNi matrix. The yield strength of (CoCuFeNi)₈₅W₁₅ was increased by ~46% with minor reduction in ductility compared with CoCuFeNi HEA. The strengthening mechanisms for (CoCuFeNi)₈₅W₁₅ included solid solution strengthening, grain refinement strengthening as well as second phase strengthening. The ductility of (CoCuFeNi)₈₅W₁₅ was resulted from grain size refinement and the plasticity of W particles and CoCuFeNi.