The Effect of Radial-Shear Rolling on the Microstructure and Mechanical Properties of Technical Titanium

Abstract

Improving the quality of hardware through the improvement of the microstructure is one of the main trends of modern metallurgy. This approach allows us to achieve special properties without the expense of expensive alloying additives. The basic idea is to grind the grain structure of the material to a size less than 1 μm. At the specified grain sizes, the hardening properties begin to manifest with a relatively small loss of plasticity. In this case, one can speak of ultrafine-grained (UFG) materials. This direction is especially important for areas of science and technology, where there are very strict requirements for the size and weight of parts with their high strength. These are aerospace engineering and medicine (implantology and orthopedics). Therefore, it makes sense to conduct research primarily on relevant materials. Titanium is known for its biological inertness, therefore it is the basis for prosthetics. In this work, the experiments on technically pure titanium using a technology close to industrial implementation, were performed. An experiment, in which a lengthy number billet at a temperature of 500 °C rolled from a diameter of 30 mm to a diameter of 15 mm in the mill SVP-08, was conducted. After that, the billet was cooled with water, and samples for studying the microstructure and samples for studying the mechanical properties, were prepared. Analysis of the microstructure showed the presence of an equiaxial ultrafine-grained structure in the peripheral areas of the work-piece and the presence of an elongated fibrous texture in the axial zone. The strength of the work-piece has increased by more than 1.5 times, while the plasticity has decreased not so much.