Dynamic pressing of titanium for producing an ultrafine-grained structure

摘要

Dynamic equal-channel angular pressing, a new method for the intense plastic deformation of materials, was developed and applied to titanium, as an example. A sample, accelerated in a gun to a velocity of 300 m/s, impinged on a matrix with intesecting channels. The deformation of titanium occurred at a shear-deformation rate of 10(4)-10(5) s(-1) stop and pressure of several GPa. Upon deformation, the strength of titanium increased by a factor of 2, with the plasticity remaining at an acceptable level. Metallographic and electron microscopy analyses demonstrated that, under the action of intense deformation, the initial course-grained structure of titanium transforms into an ultrafine-grained one.