In the present study, strain-rate and temperature dependence of the transverse tensile failure mode of unidirectional heat-resistant carbon fiber-reinforced plastics is numerically simulated by finite element analyses. In the analyses, interface failure and matrix failure are represented by cohesive zone modeling and continuum damage mechanics, respectively. For the continuum damage mechanics, Christensen's failure criteria of multi-axial stress states for each strain rate are applied to the matrix properties. Interfacial properties which are obtained by microbond test are introduced into cohesive zone modeling. A time-temperature superposition principle approach is applied in order to translate the difference in temperature as the difference in strain rate. The damage initiation depends on strain rate and temperature, while the cohesive zone modeling is assumed to be temperature- and time-independent. The initial damage starting points and the failure mode are predicted in numerical analysis. The transverse tensile strengths in analysis results are compared with the three-point bending testing results.

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