Effect of Equal Channel Angular Pressing on the Fracture Behavior of Commercially Pure Titanium

This article focuses on the effect of equal channel angular pressing (ECAP) on the fracture behavior of a commercially pure (CP) Ti. Standard mechanical tensile and fracture tests are performed at room temperature and 250 °C to determine the tensile mechanical properties and the J-∆a curves. The effect of temperature on the fracture properties, namely, the fracture toughness, the slope of the J-∆a curves, the total crack growth resistance, and the stability of the crack propagation before and after ECAP is investigated. Quantitative analysis of the fracture surfaces is performed using an automatic fracture surface analysis system. The energy required to form the fracture surface is estimated. The yield stress and the ultimate tensile stress are significantly increased by ECAP. However, similar to the case of other strengthening procedures, the fracture toughness decreases after ECAP.