Effect of temperature on the fracture toughness of A516 Gr70 steel

Fracture toughness JIC and KIC tests were performed on A516 Gr70 carbon steel plate at the temperature ranging from −160°C to 600°C, and test results were analyzed according to ASTM E 813 and ASTM E 399. Unloading compliance J-integral tests were performed on ITCT specimens. The relation between the J_IC value and the test temperature was obtained. It was concluded that the temperature ranging from −15°C to 600°C is the upper shelf region of ductile-brittle transition temperature, and in this temperature range, fracture toughness J_IC values decreased with increasing temperature. The ductile brittle transition temperature of the material may be around −30°C. In the region near −30°C, the tendency of J_IC to decrease with decreasing temperature was significant.