Experimental Estimation of J Resistance Curves From Load-CMOD Record for FFCT Specimens

摘要

Fracture toughness of ductile materials is often characterized by J resistance curves. It is generally required to adopt load line crack mouth opening displacement (CMOD) records in load line compact tension (LLCT) specimens to calculate the J integral according to ASTM E1820-13e1. However, in some cases, for example in nuclear engineering, due to material size limitations, a standard test specimen size is not achievable, and attaching or mounting the displacement transducer to measure the load line CMOD (LLD) of a smaller compact tension specimen is very challenging, and an alternative approach is required. The present study is aimed at evaluating the use of front face CMOD (FFD) records in front face compact tension (FFCT) specimens to estimate J resistance curves. Results are compared with those using LLD-based J calculations for P92 steel. It is shown that J resistance curves determined from the two approaches are in good agreement.