Abstract
Binary and ternary transition metal carbides are stable ceramic crystals with outstanding mechanical properties. In recent years, multi-component single-phase high entropy alloys (HEAs) enjoyed explosive growth due to many of their outstanding physical properties with its large and flexible composition space. Hence the composite between them can be advantageous in forming a new class of ceramic materials with combined superiority in their properties for many applications. On the basis of a systematic large-scale ab initio simulations using density functional theory that are specifically designed for their compositional variations, subtle differences in their structures, electronic and mechanical properties are revealed and discussed in detail. Fifteen supercell models with 512 atoms with equal composition of C and HEAs occupying the sub-lattices of the rock-slat structure were constructed. These models are fully optimized, and their properties carefully characterized, compared and contrasted. By applying the novel concept of total bond order density and its partial components, the partial bond order density, we revealed many subtle variations in their properties that have not been known before. This large database can play an important and valuable role in the design and synthesis of high entropy ceramic carbides.
Highlights
Following the pioneer work less than two decades ago (Senkov et al, 2013; Zhang et al, 2014; Sun et al, 2017; Ding et al, 2018), high entropy alloys (HEAs) is a flourishing research area in metal alloys with no insight
We extend the above ab initio simulation on pure HEAs to HEA-carbide composites in the FCC rock salt (NaCl) structure that retain the short-range-orders in binary carbides
Group 1 or model m1 is the main focus of HEA-carbide of the present work since other models are the derivatives of this model
Summary
Following the pioneer work less than two decades ago (Senkov et al, 2013; Zhang et al, 2014; Sun et al, 2017; Ding et al, 2018), high entropy alloys (HEAs) is a flourishing research area in metal alloys with no insight. It should be pointed out that there are many recent works in which a small amount of C, usually less than 5 atomic %, are added to mostly FCC HEAs such the as the standard Canton alloy CrMnFeCoNi (Stepanov et al, 2016; Cheng et al, 2017; Wang et al, 2017; Ikeda et al, 2019) to investigate the resulting local structural variations, formation of microstructures and precipitates and potential enhancement of their properties These works are completely different from the HEAs-carbides composites in which C constitute 50% of the lattice sites. The G/K ratio called Pugh ratio (Pugh, 1954) is a useful parameter based on simple empirical arguments on poly crystalline samples (Zhou et al, 2017), it was claimed that for G/K ratio greater (less) than 0.571, the material is more brittle (ductile)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
