Continuum damage mechanics is applied to compute fracture J-initiation and J-Resistance （J-R） curve for 20MnMoNi55 material by analyzing TPB and CT specimens. A strong mesh dependency of Gurson model is observed. Th...Continuum damage mechanics is applied to compute fracture J-initiation and J-Resistance （J-R） curve for 20MnMoNi55 material by analyzing TPB and CT specimens. A strong mesh dependency of Gurson model is observed. The exponential form of q2 parameter shown earlier near crack tip is further modified to have a variable asymptotic value q2a away from crack tip. The asymptotic value q2a is suggested to be a function of crack-tip mesh size to overcome mesh dependency of J-R and load-displacement curves. The relation between q2a with the normalized crack-tip mesh size is determined numerically for CT and TPB specimens.展开更多
文摘Continuum damage mechanics is applied to compute fracture J-initiation and J-Resistance （J-R） curve for 20MnMoNi55 material by analyzing TPB and CT specimens. A strong mesh dependency of Gurson model is observed. The exponential form of q2 parameter shown earlier near crack tip is further modified to have a variable asymptotic value q2a away from crack tip. The asymptotic value q2a is suggested to be a function of crack-tip mesh size to overcome mesh dependency of J-R and load-displacement curves. The relation between q2a with the normalized crack-tip mesh size is determined numerically for CT and TPB specimens.
