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Ti2−xNiCoSnSb (x = 0.125, 0.250, 0.375, and 0.500) half Heusler (HH) high-entropy thermoelectric alloys were synthesized by the arc melting—ball milling—spark plasma sintering route. The impact of secondary phase content on the thermoelectric properties in these alloys was examined. Ni-rich intermetallic (Ni3Sn2, Ni3Sn4) compounds were observed; the intermetallic content increased for lower Ti content, e.g., Ti1.5NiCoSnSb. A Ni-rich full Heusler (FH) secondary phase was also observed. These results were consistent with first-principles calculations that show that the formation enthalpy of Ti1.5NiCoSnSb was higher than that of Ti2NiCoSnSb and the full Heusler (FH) TiNi2Sn phase. In lower Ti content samples, the electrical conductivity increased, and lattice thermal conductivity decreased at the expense of thermopower owing to higher FH and the Ni3Sn2 phase content. Ti1.5NiCoSnSb exhibited lower lattice thermal conductivity of 3.5 W/mK, compared to 5.4 W/mK at 823 K for Ti2NiCoSnSb due to increased phonon scattering at HH/Ni3Sn2 interfaces. But considering the decreasing power factor with lower Ti content, the maximum ZT obtained in Ti1.875NiCoSnSb (0.171 at 973 K) was only marginally higher than the value for Ti2NiCoSnSb. Further, compositional tuning is hence necessary to maximize the power factor. [ABSTRACT FROM AUTHOR]

An upsurge in demand and extensive effort in orthopedic implants directed toward innovative biomaterials for orthopedic applications. Orthopedic implants are significantly used in mature alternatives to retain, restore or modify the defective bone or tissue. However, exhaustive research in the past reveals various health-associated problems that can be effectively overcome by inventing newer kinds of biomaterials. The selection of optimal materials and the fabrication process are crucial challenges enforced by numerous novel materials that could be made for orthopedic applications. This paper intends to systematically assess the processing method employed in manufacturing the biomaterials for orthopedic applications. However, the success of biomedical implants in orthopedic are commonly restricted owing to insufficient bone-implant integration, wear debris induced osteolysis, and implant-associated infections. Nevertheless, the endeavor has also been intended to enhance the biological properties of the biomaterials by surface modification process while retaining their strength and hardness. Furthermore, various surface modifications have been comprehended. This review conferred contemporary advancements in surface coating approaches in orthopedic to enhance their osteointegration, improve corrosion resistance and accomplish antibacterial performance, clinical success and long-term service. The insight review has revealed the current outcomes in the field of engineering biomaterials concerning surface modifications of metallic implants or composite for enhancing their biological properties. [ABSTRACT FROM AUTHOR]

Sn-doped TiFe0.5Ni0.5Sb1−xSnx (x = 0, 0.05, 0.1, 0.2) were synthesized by vacuum arc melting (VAM). In addition to the half-Heusler phase, secondary phases of Fe–Sb-rich compound and Ti-rich compounds were obtained after VAM. The alloys were then subjected to ball milling for 1 h and 5 h. Ball milling for 1h led to microcrystalline grains, while that for 5 h led to nanocrystalline grains. Ball milling followed by spark plasma sintering (SPS) at 1173 K led to significant reduction in size of secondary phases in the microstructure. The undoped sample exhibited a ZT of 0.008 at 873 K for both 1h and 5h BM-SPS samples. [ABSTRACT FROM AUTHOR]

Herein, the influence of carbon nanoparticle addition on the selective laser melting (SLM) behavior and the resultant properties of gas‐atomized CuCr0.3 powder are investigated. The carbon addition neither affects the powder flowability, nor its packing density, but it significantly enhances the optical absorption for infrared radiation. Despite the improved optical absorption of the powder bed after carbon addition, a comparable SLM behavior is observed for both virgin and carbon‐mixed CuCr0.3 powders. Furthermore, the addition of carbon nanoparticles facilitates in situ deoxidation of copper and chromium oxides present in the CuCr0.3 powder. Accordingly, a larger fraction of chromium is obtained in its metallic form in the as‐built carbon‐mixed CuCr0.3 part. The presence of metallic chromium allows tailoring of the mechanical and electrical properties by postheat treatments (HTs). The best combination of mechanical (tensile strength of 298 ± 19 MPa, yield strength of 208 ± 18 MPa, ductility of 21 ± 4%) and electrical (87 ± 1% international annealed copper standards [% IACS]) properties is realized for the carbon‐mixed CuCr0.3 alloy after a direct age hardening HT. The improvement in mechanical properties is attributed to the precipitation of nanometer‐sized, coherent, and metallic chromium precipitates in the copper matrix. [ABSTRACT FROM AUTHOR]