Fundamental design strategies for advancing the development of high entropy alloys for thermo-mechanical application: A critical review
Ufoma Silas Anamu, Olusoji Oluremi Ayodele, Emmanuel Olorundaisi, Bukola Joseph Babalola, Peter Ifeolu Odetola, Anthony O. Ogunmefun, Kingsley Ukoba, Tien‐Chien Jen, Peter Apata Olubambi
Abstract
Nearly three decades since the discovery of high entropy alloys (HEAs), it has greeted a broad interest in the field of materials research as a better alternative to conventional alloy materials due to the exceptional combinatorial properties they offer in terms of lightweight, high-specific strength in elevated temperatures, excellent oxidation and corrosion resistance properties (among others). Leveraging on the “four core effects”: high-entropy effect, sluggish/hysteretic diffusion effect, severe-lattice-distortion effect and cocktail effect which define the special features responsible for their outstanding properties, HEAs have been successfully employed for high-temperature applications in automobile and in the aerospace. An emerging sub-field of HEAs is the incorporation of a secondary strengthening phase that can be provided by the precipitation of intermetallic (IM) compounds to enhance the microstructure which will concomitantly affect the properties of a material (thermal, chemical and mechanical properties) for broader engineering applications. In this article, design concepts brewed from thermo-physical parameters calculation and computational thermodynamics using a CALPHAD-based tool were reviewed as fundamental design strategies in the development of IM-containing HEAs.