The effect of temperature on the strength of a multiphase high-entropy 30Fe–30Cr–20Co–10Mo–10W (at %) alloy, which is prepared by sintering of elemental powders preliminary mechanically alloyed in an argon atmosphere, is investigated. The ultimate compression strength is shown to remain almost unchanged in a temperature range of 77–1123 K and is ≈1550 MPa; in this case, the brittle failure mechanism is observed. The subsequent heating to 1273 K promotes the dissolution of the brittle σ phase, which ensures the increase in the plasticity and leads to the abrupt decrease in the ultimate strength to 265 ± 4 MPa and the hardness from 612 ± 15 to 60 ± 2 MPa.
Ivannikov et al. (Thu,) studied this question.