A promising new class of multi-component alloys with exceptional mechanical properties

Abstract

A non-equiatomic FeCr1.2NixAl alloys were introduced and characterized employing various characterization techniques. The great application prospect is expected because of their high mechanical properties and superior specific strength. In this study, the effect of Ni addition on the microstructure, mechanical properties and work-hardening behavior at room and high temperatures have been systematically investigated. Dual phases of ordered (Ni, Al) structure and disordered [Fe, Cr] structures are involved in alloys. The EDS analysis indicates the formation of Fe/Cr-rich regions in interdendrite and Ni/Al-rich regions in grains. The alloys show remarkable advantages in density and microhardness. The experimental results show that the Ni addition significantly increases the compressive strength of the as-cast alloys attributed to the solution strengthening and fine grain strengthening, and more importantly, simultaneous enhancements in specific strength. However, the additive Ni is found to cause a little decrease at high temperature owing to the crystal boundary weakening, accompanied with a decline in specific strength. The alloys possess higher work-hardening ability rather than many other alloys and metallic materials. The value of work-hardening exponent and capacity slightly increase with the additive Ni and the FeCr1.2Ni1.3Al alloy performs the most desirable. Due to these significant advancements, the proposed alloys are attractive for use in aerospace and automotive technology fields.