王忠远1,2 江善元1,2 王振军1,2 杨思远1,2 张奥迪1,2周金秋1,2 蔡长春1,2
Micromechanical Analysis on the Effect of Fiber Content on Transverse Tensile Behavior and Damage Evolution of Unidirectional Carbon Fiber Reinforced Aluminum Composites
Wang Zhongyuan1,2, Jiang Shanyuan1,2, Wang Zhenjun1,2, Yang Siyuan1,2, Zhang Aodi1,2, Zhou Jinqiu1,2, Cai Changchun1,2
(1.National Defence Key Discipline Laboratory of Light Alloy Processing Science and Technology, Nanchang Hangkong University; 2.School of Aeronautical Manufacturing Engineering, Nanchang Hangkong University)
Abstract: The microscopic damage and macroscopic mechanical behavior of Cf/Al composites with different fiber content were investigated by micromechanical and experimental method. Representative Volume Element (RVE) with diagonal regular quadrilateral and regular hexagonal fiber arrangements were established according to the composites microstructure. The damage behavior of matrix alloy was described by ductile damage model and the fiber fracture behavior was simulated using a maximum stress failure criterion. And then a micromechanical finite element model based on cohesive interface was established and the calculation reliability was verified by the experimental results. Based on the micromechanical model, the damage evolution and fracture behavior of the composites with different fiber content were analyzed. It is found that the micromechanical model with regular hexagonal fiber arrangement can predict the elastoplastic behavior of composites accurately. At the first stage, the initial interface damage is accumulated with the increase of strain and induce some local interface failure. At the middle stage, some local matrix damage is initialed and developed near the failed interface. At the last stage, the interface and matrix failure results in the transverse cracking of the composites. The tensile fracture surface exhibits the characteristic of interfacial debonding and matrix tearing. The transverse tensile modulus and ultimate strength of the composite are decreased with the increase of fiber content, which can be attributed to the occurrence of more interface quantity and interface area.
Key Words: Cf/Al Composites, Micromechanics, Damage Evolution, Fiber Content, Mechanical Properties