High throughput construction for the deformation mechanism diagram and dynamic recrystallization of a bimodal‐sized particle‐reinforced Ti‐2.5Zr‐2Al‐1(Si,C) titanium alloy

Abstract

An in situ autogenous particle‐reinforced Ti‐2.5Zr‐2Al‐1(Si,C) titanium alloy is prepared by vacuum induction melting. The wide range of an effective strain between 0.2 and 1.2 and the corresponding microstructure are obtained by the double‐cone high‐throughput compression test and finite element simulation. The deformation mechanism diagram with strains of 0.2–1.2 and strain rates of 0.7–1.5 s−1 at 900°C is constructed. When the strain rate is 1.3 s−1, dynamic recovery occurs in the small strain range (<0.377), dynamic recrystallization (DRX) occurs in the medium strain range (0.377–1.182), and deformation instability occurs in the large strain range (>1.182), resulting in the deformation bands. High‐angle annular dark field and high‐resolution transmission electron microscopy are used to determine the existence of bimodal particle distribution, namely micron‐scale TiC particles and nano‐scale Ti5Si3 and (Zr, Si) particles. The average radius of the (Zr, Si) nanoparticles measured by small angle neutron scattering is 19.3 nm, and the volume fraction is 0.35%. DRX grains with an average size of 0.49 μm are obtained at 900°C, strain rate of 1.3 s−1, and strain of about 0.6. Micron‐scale particles stimulated DRX nucleation, while nanoscale particles hindered the growth of new grains, resulting in grain refinement.