METALLIC MATERIAL HAVING ULTRA-FINE GRAIN STRUCTURE AND METHOD FOR ITS MANUFACTURE

摘要

A method for producing a metallic material having anultra-fine microstructure, the metallic material exhibiting aphase transformation of a low-temperature phase into a high-temperature phase is disclosed, the method comprising thesteps of:preparing a metallic material which comprises at least alow-temperature phase;applying plastic deformation to the metallic material;andincreasing the temperature of the metallic material to apoint beyond a transformation point while applying the plasticdeformation to effect reverse transformation of the low-temperature phase into a high-temperature phase.