Effect of Fe–Co–Cr Content and Mechanical Activation on Ni–Al–(Fe–Co–Cr) Combustion

This paper describes the study of the effect of mechanical activation and amount of a Fe + Co + Cr binder on burning rate, maximum temperature, sample elongation during combustion, composite particle size after activation, mixture yield after activation, and phase composition and morphology of synthesis products in a Ni–Al–(Fe–Co–Cr) mixture. Mechanical activation of a Ni + Al +  \(x\) (Fe + Co + Cr) mixture allows for samples to burn at room temperature with a Fe + Co + Cr binder content of up to 40%. Activating the mixtures increases burning rate, combustion temperature, sample elongation, and sample porosity; however, the sample strength decreases. An increase in the Fe + Co + Cr binder content in the activated Ni + Al +  \(x\) (Fe + Co + Cr) mixture makes the mixture yield after mechanical activation greater, reduces the composite particle size, and elongates the synthesis product samples. The burning rate of activated mixtures nonmonotonically depends on the Fe + Co + Cr binder content and has a maximum at a binder content of 10%. High-entropy alloys, which are solid solutions based on NiAl and Ni₃Al intermetallic compounds, are synthesized using self-propagation high-temperature synthesis.