Abstract
The present study investigates the impact of Mo and Nb on the characteristics of CoCr sintered alloys, with a specific focus on their potential for biomedical applications. Cobalt-chromium-based alloys (namely, Co-Cr-2.5Mo-2.5 Nb, Co-Cr-3Mo-3 Nb, and Co-Cr-3.5Mo-3.5 Nb) were fabricated using sintering conditions comprising a heating rate of 200 °C/min, pressure of 50 MPa, temperature of 1100 °C, and a dwell period of 15 minutes. The findings indicated that the CoCr alloy, when supplemented with Mo and Nb, exhibited a singular-phase composition consisting mostly of a face-centered cubic (FCC) core comprised of gamma-Co, accompanied by a minor proportion of a hexagonal close-packed (HCP) solid solution matrix known as epsilon-Co, and interspersed with precipitates. The inclusion of Co-Cr-3Mo-3 Nb alloy composition resulted in the highest relative density of 97.56 % compared to other alloy compositions, indicating its optimum alloying properties. The Co-Cr-3Mo-3 Nb alloy had the maximum polarization resistance of 522.52 Ω, indicating a strong resistance to corrosion. Additionally, it displayed the least corrosion rate of 1.5904 mm/year. The ternary alloy consisting of Co-Cr-3.5Mo-3.5 Nb demonstrated superior resistance to the applied indentation stress, as shown by its minimal maximum penetration depth of 372.23 nm and the lowest average coefficient of friction (COF) values.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have