The Influence of Equal Channel Angular Pressing on Structure and Mechanical Properties of New β-Ti Alloy Ti–10Mo–8Nb–6Zr

This work presents comparative studies of structural and mechanical properties of a new β-Ti alloy Ti–10Mo–8Nb–6Zr exposed to conventional cold rotational forging and equal channel angular pressing (ECAP) at 250°C. The main phase in the initial quenched state after forging and ECAP is the BCC β phase. Broadening of X-ray lines of the β phase and TEM data indicate refinement of structure and increase in concentration of lattice defects after deformational treatment. In the initial state, the alloy has ultimate tensile strength of about 700 MPa, the yield stress of 450 MPa, and relative elongation to failure of ~30%. As a consequence of forging, the ultimate strength and yield stress of Ti–10Mo–8Nb–6Zr alloy increase to 1230 and 950 MPa, and after ECAP, they increase to 1280 and 1270 MPa, respectively; also, the relative elongation decreases to 6%. Significant improvement of strength properties of Ti–10Mo–8Nb–6Zr alloy exposed to ECAP makes it more promising for application in the medical field.