A novel method to predict the stress-strain curves and J resistance curves of ductile materials by small samples. (May 2019) - Peng, Yun-qiang
Abstract: In this study, a small punch testing (SPT)-related stress-strain relation (SPT-SR) model was used to obtain the stress-strain curve of P92. After that, a critical fracture criterion was obtained by SPT and notched small punch testing (NSPT) specimens according to the stress-strain curve of P92 determined by SPT-SR model. The result demonstrates that it is in accord with the criterion obtained by different configurations using the stress-strain curve obtained by finite-element-analysis aided testing (FAT) method. Finally, a J resistance curve of P92 for small C-shaped inside edge-notched tension (CIET) specimen was predicted based on finite element simulations and the fracture criterion determined by SPT and NSPT specimens, which shows an agreement with the J resistance curves obtained by experiments. Consequently, this work proposes a good approach to determine the stress-strain curves and J resistance curves of ductile materials by small samples without any relations to large size samples. Highlights: Determine the stress-strain curve of P92 by SPT-SR model. Obtain the fracture criterion of P92 by small specimens according to the stress-strain curve determined by SPT-SR model. Predict the J resistance curve of small CIET specimen based on the critical fracture criterion.