复合材料层合板热-力作用下的失效研究

碳纤维复合材料力学性能优异,在航空航天等领域广泛使用,其在热-力联合作用下的损伤失效研究对于结构的损伤破坏和强度预测具有重要意义。发展了热力耦合条件下复合材料结构渐进损伤分析方法,建立了三维有限元热烧蚀模型,并验证了计算模型的可靠性;采用三维Hashin失效准则,结合材料刚度突然退化模式,建立了失效分析模型,仿真分析了热-力联合作用下复合材料层合板损伤演化全过程。结果表明,该方法不仅能够较好地模拟复合材料层合板从局部失效的萌生、扩展直至结构完全失效的全过程,而且可以直观地显示结构的损伤失效模式,预测结构在不同条件下的承载能力。

Failure Study of Composite Laminates under Thermal-mechanical Loads

Carbon fiber composites have been widely used in the fields of aerospace and other fields because of its good mechanical property. The damage failure of composites under thermal-mechanical coupling conditions is of great significance for damage and strength prediction of structures. A three dimensional finite element model considering ablation is established for the Progressive damage simulation of the composite structure under thermal-mechanical coupling conditions, and the reliability of the model is verified. Based on the failure criterion of three-dimensional Hashin failure criterion and the abrupt degradation of material stiffness, a failure analysis model is established. The whole process of damage evolution of composite laminates from the beginning of the damage to ultimate failure under thermal-mechanical coupling is simulated. The results show that the method can simulate the failure of composite laminates from the beginning of the damage to grow completely broken of the structure of whole process. It also can display the failure mode of the structure intuitively and can predict the bearing load of the structure under different conditions.