Research on Crack Propagation Behavior of Gas Pipeline Steel

摘要

Based on the theory of hydrogen enhanced localized plasticity of the hydrogen induced cracking and considered the effect of residual stress produced by eliminated stress heat-treatment, a fractal model of hydrogen induced cracking was presented, and a relationship among the effective surface energy Γ(H), fractal dimension D and stress intensity factor of hydrogen induced cracking, K_(IH), for welding pipeline under hydrogen environment was set up, from which the relationship of D and K_(ISCC) is obtained. The model was verified experimentally to be correct.