Ultrafine-grained pure titanium is characterized by its exceptional mechanical properties, among which high ultimate strength and high yield value are of utmost importance. Equal channel angular pressing (ECAP) and ECAP+cold extrusion (CE) have been used to process ultrafine-grained pure titanium.
Though many aspect studies on the mechanical deformation behavior of ultrafine-grained (UFG) pure titanium have been carried out, there is little study on systematic qualitative and quantitative characterizations on the temperature-dependent deformation and fracture features of pure titanium processed by ECAP and CE.
The study on the temperature-dependent deformation and fracture features of ultrafine-grained materials is of great interest because of their limited application temperature.
Yun Jong Guk, a section head at the Faculty of Mechanical Science and Technology, investigated the tensile deformation and damage behavior and microstructures of ultrafine-grained (UFG) pure titanium processed by ECAP and ECAP+CE at different temperatures, and carried out quantitative fractal analyses of deformation and damage morphologies by the yard-stick method based on Mathematica.
The results show that as the temperature increases, the diameter and depth of dimples on the fracture surfaces of ultrafine-grained pure titanium increase significantly with corresponding increase in the fractal dimensions. The microstructure observation results of the tensile deformation show that the dislocation density decreases significantly with increasing temperature and the grain boundaries become clear.
For more information, please refer to his paper “Temperature-Dependent Tensile Deformation and Fracture Features of Commercially Pure Ti Processed by ECAP and Cold Extrusion” in “Proceedings of KUTIC-2025”.