Ti-containing high entropy alloys: Competitors to Superalloy 718

Superalloy 718 is ubiquitous to aeroengine applications owing to its ultra-high-strength, thermal stability, weldability, formability, etc. Currently, the relatively lighter Ti-containing high entropy alloys, having a unique combination of elevated and ambient temperature mechanical properties and corrosion resistance, are projected as competitors to superalloy 718. Hence, Ti-containing high entropy alloys are being investigated for various potential applications, including elevated temperature, biomedical, extreme environments, and so forth. We analyzed the available data in the literature for the titanium-containing high entropy alloys for applications in aeroengines to unearth the composition-processing-microstructure-property relationships by materials informatics. We applied fundamental statistical analysis, advanced statistical analysis, including principal component analysis and hierarchical clustering, and multiple attribute decision making to hear the voice of the data. The ranks assigned by several multiple attribute decision making methods, including but not limited to the technique for order of preference by similarity to ideal solution (TOPSIS), weighted Euclidean distance (WEBDA), range of value method (ROVM), multiplicative exponent weighing (MEW), and additive ratio assessment (ARAS) were consistent. The fundamental and advanced statistical analysis not only consolidated the ranks of the alloys from various multiple attribute decision making methods but also identified differences and similarities among the top-ranked alloys. The ranks of the alloys varied when relative weights of various properties were varied, which revealed several Ti-containing high entropy alloys' potential to substitute a range of aeroengine parts. The analyses suggest potential replacement substitutes and provide possible directions for the design and improvement of Ti-containing high entropy alloys. The likely replacement substitutes could be investigated for various parameters, and then further development would be possible by the suggested directives from this investigation.