Structure and properties of a laminated composite material made of high-entropy alloy with carbide and intermetallic hardening

摘要

A composite material obtained via the diffusion welding of a multilayer sandwich of foils of highentropy (HE) FeCoNiMnCr alloy and foils of Al–Si alloy is studied. After pressure welding, diffusion layers of Me(Al, Si), Me2(Al, Si) and Me_3(Al, Si) intermetallic compounds are generated instead of AlSi alloy. During welding, the external foils of HE alloy can also carbonize with the generation of carbide deposits based on chromium as the most carbide-forming element. Mechanical bend tests are performed in the range of 750–950°C, showing that the limit of proportionality of the obtained composite material up to 950°C remains steady in the range of ~665 ± 120 MPa, with a maximum strain of 920 ± 155 MPa. The results from prolonged thermal creep tests are presented. In terms of its high temperature properties, the resulting material can be compared to state-of-the-art alloys based on the Ti–Al family that have operating temperatures of up to 750–800°C. This level can be raised even higher, to 900–950°C.