Аннотация
Titanium and titanium alloys are widely used materials, particularly in the medical and aerospace industries where increasing strength is critical. One of the methods to increase the strength of titanium is to refine its structure, for example, through severe plastic deformation. However, the existing methods of severe plastic deformation can refine the structure to an ultra-fine grain size, but they are not continuous and are difficult to implement in real-world production settings. Asymmetric rolling of a range of metallic materials offers a solution to this problem by producing long, thin-sectional semi-finished products with an ultra-fine grain structure. So, the aim of this paper is to evaluate the possibility of structural refinement of high-strength Grade 4 titanium by asymmetric rolling and the effect of subsequent annealing temperature on mechanical properties. The paper investigates flat rolling with kinematic asymmetry. Deformation was carried out in single pass at room temperature with a fivefold of the speed working rolls ratio, which was accompanied by post-deformation annealing. The structural refinement of titanium after the asymmetric rolling was evaluated using transmission electron microscopy. Also, the mechanical properties by tension were tested and the microhardness of the samples before and after asymmetric rolling were measured. It has been shown that asymmetric rolling at room temperature reduces the average grain size of the initial coarse-grained Grade 4 titanium by two orders of magnitude, increases the yield and tensile strengths by more than one and a half times and increases the microhardness. Post-deformation annealing at 400 – 450°C further increases the microhardness and strength properties. Annealing at 500°C forms a grain structure that reduces the microhardness and strength but maintains a high elongation.
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Финансирование на английском языке
1. A.A. Blagonravov Mechanical Engineering Research Institute of the Russian Academy of Sciences - he State Assignment funds, code (cipher) of the scientific topic FFGU-2026-0003
2. the Russian Science Foundation (Nosov Magnitogorsk State Technical University) - № 25-79-31018, https://rscf.ru/project/25-79-31018