The longitudinal tensile properties of SiCf/Ti-6Al-4V composites with different fiber volume fractions were simulated by the Monte Carlo 2-D finite element model. The random distribution of fiber strength was expresse...The longitudinal tensile properties of SiCf/Ti-6Al-4V composites with different fiber volume fractions were simulated by the Monte Carlo 2-D finite element model. The random distribution of fiber strength was expressed by the two-parameter Weibull function. Meanwhile, contact elements and birth-death elements were used to describe the interfacial sliding process after debonding and fiber breakage（or matrix cracking） respectively, which was realized by subroutine complied in ANSYS-APDL（ANSYS Parametric Design Language）. The experimental results show that the yield stress and ultimate tensile strength of SiCf/Ti-6Al-4V composites increase with increasing fiber volume fraction, while the corresponding strain of them is just on the contrary. In addition, almost the same failure mode is obtained in SiCf/Ti-6Al-4V composites with various fiber volume fractions when the interfacial shear strength is fixed. Finally, the tensile strength predicted by finite element analysis is compared with that predicted by Global load-sharing model, Local load-sharing model and conventional rule of mixtures, thus drawing the conclusion that Local load-sharing model is very perfect for the prediction of the ultimate tensile strength.展开更多
基金Funded by the National Natural Science Foundation of China(51271147)
文摘The longitudinal tensile properties of SiCf/Ti-6Al-4V composites with different fiber volume fractions were simulated by the Monte Carlo 2-D finite element model. The random distribution of fiber strength was expressed by the two-parameter Weibull function. Meanwhile, contact elements and birth-death elements were used to describe the interfacial sliding process after debonding and fiber breakage（or matrix cracking） respectively, which was realized by subroutine complied in ANSYS-APDL（ANSYS Parametric Design Language）. The experimental results show that the yield stress and ultimate tensile strength of SiCf/Ti-6Al-4V composites increase with increasing fiber volume fraction, while the corresponding strain of them is just on the contrary. In addition, almost the same failure mode is obtained in SiCf/Ti-6Al-4V composites with various fiber volume fractions when the interfacial shear strength is fixed. Finally, the tensile strength predicted by finite element analysis is compared with that predicted by Global load-sharing model, Local load-sharing model and conventional rule of mixtures, thus drawing the conclusion that Local load-sharing model is very perfect for the prediction of the ultimate tensile strength.
