Composition-dependent elastic modulus, corrosion resistance, and misfit contributions to solid solution hardening of near β-Ti(Mo) alloys
摘要
A comprehensive correlative study is conducted on the Ti–Mo system to optimize the composition for the applications of biological stents examining the phase stability, microstructure, mechanical, and corrosion properties. The alloys up to 30 at.% Mo exhibited the presence of a single phase, β, while the other alloys also contain the α phase. Hardness and elastic modulus showed a linear increase up to 40 at.% Mo and decrease thereafter. Size misfit deemed to be the dominant factor for the solid solution hardening behavior of the alloys compared to the modulus misfit as examined through the Labusch and Fleischer models. The Ti(20 at.% Mo) alloy shows the best corrosion resistance in the medium of 0.9 wt.% NaCl solution followed by the ones containing 10 at.% Mo and 40 at.% Mo. A 3-D comparative map of elastic modulus-corrosion rate-specific hardness showed that the Ti(20 at.% Mo) alloy would be suitable for the biological stents trading off all the properties studied in the present work.
Graphical abstract