Cryogenic Effects on the Fracture Behavior of Forged JJ1 Type Austentic Stainless Steel Plate

摘要

This paper discusses the fracture toughness and the temperature rise of forged JJ1 type austenitic stainless steel plate at liqid helium temperature for fusion reactor magnetis of the next generation. Elastic-plastic fracture toughness (J_IC) tests were conducted in general accordance with ASTM E813-81 and E813-87, and the unloading compliance technique was applied using 12.5- and 25-mm-thick compact tension specimens. Thermocouples were used to measure the temperature rise near the crack tip. The effects of specimen size and side-groove on the cryogenic fracture properties of this alloy, and the temperature rise during dynamic crack growth are examined. The effect of inclusion content on the fracture mechanics parameters (J_Q, J_IC) is also discussed using a scanning electron microscopy (SEM) and a energy dispersive X-ray spectrometer (EDX).