Computational design of corrosion-resistant and wear-resistant titanium alloys for orthopedic implants

Titanium alloys are promising candidates for orthopedic implants due to their
mechanical resilience and biocompatibility. Current titanium alloys in orthopedic
implants still suffer from low wear and corrosion resistance. Here is presented a
computational method for optimizing the composition of titanium alloys for enhanced
corrosion and wear resistance without compromising other properties of the alloy such
as phase stability, biocompatibility, and strength. The cohesive energy, oxide formation
energy, surface work function, and the elastic shear modulus of pure elements are used
as proxy descriptors to guide the design of the alloys with enhanced wear and corrosion
resistance. For the best-selected candidates, the CALPHAD approach, as implemented
in the Thermo-Calc software, is used to calculate the phase diagram, yield strength,
hardness, Pourbaix diagram, and the Pilling–Bedworth (PB) ratio. These calculations
are used to assess the thermodynamic stability, corrosion resistance,
and wear resistance of the selected alloys. Additional insight can be inferred about the
role of silicon on improving the corrosion and wear resistance of alloys, and this
computational method is being expanded into developing a similar basis of studying
High-Entropy Alloys.