α′ martensite Ti–10Nb–2Mo–4Sn alloy with ultralow elastic modulus and High strength

•α′ martensite Ti–10Nb–2Mo–4Sn alloy can perform ultralow elastic modulus.•High strength is attributed to nano-sized α′ and dislocation tangles.•The alloy has potential applications in the biomedical and industrial fields.

By alloying and thermo-mechanical treatment, a novel α′ martensite Ti–10Nb–2Mo–4Sn (wt%) alloy with ultralow elastic modulus and high strength was prepared. Coarse α′ martensite plates with internal twins are formed in the solution treated alloy. Upon a severe cold rolling deformation, the alloy exhibits fine microstructure consisting of nano-sized α′ and dislocation tangles, resulting in a remarkable increase in strength. Meanwhile, the cold rolled alloy exhibits an ultralow elastic modulus of 41 GPa, which is lower than that of most biomedical β-type Ti alloys containing a considerable amount of expensive Nb and Ta. Therefore, the α′ martensite Ti–10Nb–2Mo–4Sn alloy has a high potential not only for biomedical applications, but also for industrial applications, due to its low elastic modulus, high strength and low cost.