Optimal design and characterization of novel biomedical Zr-based alloys for hard tissue substitution

Abstract

AbstractIn this work, the quadratic regression orthogonal rotation design has been applied to optimize the composition and mechanical properties of a novel biomedical Zr-based alloy system. Combined with the statistical package for the social sciences (SPSS) analysis, a mathematical model is proposed to assess the influence of Cu, Nb and Sn contents on the elastic modulus of the alloy system. The optimal alloy composition can be determined based on the regression modeling. The experimental results exhibit the role of Nb content on mechanical properties of the Zr alloys. It is indicated that the as-cast Zr-4 at.% Cu-1.5 at.% Sn-x at.% Nb (x = 0, 7.5 and 15) alloys are mainly composed of α-Zr and Zr3Cu phases. Nb addition results in the formation of β-Zr and fine uniformly-distributed secondary phase Zr3Cu. The Zr-based alloy system exhibits low elastic modulus (19.55–32.46 GPa), moderate compression strength (1904–1117 MPa), yield strength (543–1078 MPa) and high elastic energy (7.19–18 MJ m–3). The Zr-4 at.% Cu-1.5 at.% Sn-7.5 at.% Nb alloy shows an elastic modulus of 19.55 GPa, which is comparable to that of human bones. These optimized Zr-4 at.% Cu-1.5 at.% Sn-x at.% Nb alloys can be considered as potential candidates for biological hard-tissue substitute materials.