Effect of Gd addition on phase formation, microstructure, and mechanical performance of a CoCrFeNi multi-principal element alloy

• DOI: 10.1016/j.matdes.2023.112365
• Publication Date: 2023-10-02T05:45:46Z
• Authors: Yan Long; Wenxing Meng; Florian Vogel; Guiqi Li; Lijing Zhang
• Keywords: Spark Plasma Sintering

Here, two multi-principal element alloys (MEPAs): CoCrFeNi and CoCrFeNiGd0.05 are fabricated by high-energy ball milling spark plasma sintering. The effect of Gd on microstructure mechanical properties the MPEA is investigated. addition to base alloy leads precipitation a GdNi5-type phase with hexagonal structure (HS) minor amounts Gd-rich oxide from FCC matrix. Compared alloy, grain size smaller, tensile yield strength significantly increases 546 MPa 859 MPa, along sacrifices in plasticity where elongation only slightly decreases 20.8% 19.4%. enhanced Gd-containing mainly attributed boundary strengthening ultrafine-grained contributed HS phase. Transmission electron microscopy (TEM) results demonstrate that intermetallic coherent matrix shows following orientation relationship: {11—}1—}1FCC//{—211—}9HS. high composite-structured homogenous distribution ultrafine HS-FCC interface facilitating dislocation slipping.