抄録
This investigation has been carried out to determine the influence of specimen size and side groove depth on elastic-plastic fracture toughness parameters. Elastic-plastic fracture toughness JIC and tearing modulus Tmat were evaluated by the unloading compliance method which was described in ASTM E813-81 standards. Compact tension specimens were prepared from SUS316LN and the test were conducted at cryogenic temperature 4.2K. It is understood that JIC and Tmat are independent of specimen size when the specimen satisfies ASTM standard size requirements. JIC and Tmat decrease with the increase of side groove depth for 0-12.5% of original thickness, and they are independent of side groove depth when the depth is 12.5-37.5%. These results suggest that a 0.5CT small specimen with 25% side grooves can provide proper JIC and Tmat values independent of specimen size and side groove depth.
