Xue C.,Key Laboratory of Mechanics on Disaster and Environment |
Xue C.,Lanzhou University |
He A.,Key Laboratory of Mechanics on Disaster and Environment |
He A.,Lanzhou University |
And 4 more authors.
Mechanics of Materials | Year: 2013
For a linear strain hardening material, we investigate the strain hardening effect on the crack tip opening displacement (CTOD) and obtain some interesting results. The nonlinear constitutive equation is simplified into a valid form, and a hardening function is introduced to solve this problem analytically. A new strip hardening model is proposed, and the strain hardening effect is limited in a sufficiently large zone which contains the crack. The hardening function is used to describe the degree of average strain hardening in this hardening zone for a given applied stress. Based on the strip hardening model, an analytical relationship between CTOD and remote applied stress is derived. It is interesting that both strip hardening zone size and CTOD depend on not only the applied stress, but also the hardening parameters. The theoretical results can agree with the experiments quite well by selecting an appropriate hardening function. Furthermore, the relationship between CTOD and overall strain is also obtained analytically in this paper. Compared with the experimental results, the strip hardening model is also valid to interpret the experimental results of the relationship between CTOD and overall strain. Therefore, we hope that the strip hardening model can be used to analyze more fracture behaviors for strain hardening materials. © 2013 Published by Elsevier Ltd.