Effect of extrusion temperature and extrusion ratio on grain structure, crystallographic texture, and mechanical properties of a Ti–Ag alloy

This study investigates the effects of extrusion temperature (700, 800, and 900 °C) and extrusion ratio (10:1, 16:1, and 25:1) on the microstructure, grain refinement, crystallographic texture, hardness, and tensile properties of a Ti–Ag alloy. Extrusion promoted the fragmentation and redistribution of the Ti 2 Ag intermetallic phase within the α-Ti matrix, resulting in a more homogeneous particle distribution at higher extrusion temperatures and ratios. The finest grain structure was obtained at 800 °C with an extrusion ratio of 25:1, yielding an average grain size of 7.4 µm and a recrystallized fraction of 74.8%. Increasing the extrusion ratio enhanced grain refinement, increased the fraction of high-angle grain boundaries (HAGBs), and intensified the crystallographic texture. In contrast, increasing the extrusion temperature promoted recovery and recrystallization, thereby weakening the texture. The highest hardness of 270 HV, ultimate tensile strength of 850 MPa, and yield strength of 725 MPa were obtained at 700 °C with an extrusion ratio of 25:1. At this extrusion ratio, elongation increased from 13% at 700 °C to 19% at 900 °C. Fractographic analysis revealed that increasing the extrusion ratio from 10:1 to 25:1 produced finer, less pronounced dimples, whereas increasing the extrusion temperature resulted in the formation of coarser dimples.