THERMAL STABILITY OF HIGH-ENTROPY ALLOY W1,5FECONI AT 25-1350 °С

Abstract

A high-entropy W1,5FeCoNi alloy was obtained by mechanical alloying methods within 20 hours. It is shown that during the production of the alloy, a mixture BCC / FCC solid solutions and monocarbide WC is formed. It was established that during heating of the W1,5FeCoNi alloy from 25 °C to 1350 °C, six thermal reactions are observed. Active reduction of surface oxides by carbon atoms takes place at 523 °C. Further heating shows a double exothermic reaction with two half maxima at 608 °C and 639 °C temperatures. It is shown that the high exothermic reaction between the components of the WEC is caused by chemical reactions with the formation of Laves phases. It was established that at 1257 °C the W1,5FeCoNi alloy melts due to the formation of WC-(Fe,Co, Ni) eutectics