叠层穿刺C_(f)/Al复合材料的高温拉伸性能研究

High Temperature Tensile Properties of Laminated Puncture Structural C_(f)/Al Composites

选用M40J碳纤维为增强体、ZL301铝合金为基体,采用真空气压浸渗法制备碳纤维体积分数为50%的叠层穿刺Cf/Al复合材料。主要研究了复合材料室温和高温下的经向拉伸性能,并分析了其微观组织及拉伸失效机理。结果表明,叠层穿刺Cf/Al复合材料在室温、350℃和400℃下经向抗拉强度分别为650.2、619.8和540MPa,经向弹性模量分别为81.78、72.76和60.82GPa;叠层穿刺Cf/Al复合材料在350℃和400℃下经向抗拉强度的损失率分别为4.8%和16.95%,经向弹性模量的损失率分别为11%和25.67%,在350~400℃叠层穿刺Cf/Al复合材料经向力学性能下降幅度明显大于室温~350℃;其应力-应变曲线呈非线性特征,叠层穿刺Cf/Al复合材料高温经向拉伸失效过程可分成4个阶段,即整体抗变形阶段、累积阶段、断裂失效阶段、失稳断裂阶段。

The vacuum pressure infiltration was used to prepare the laminated puncture structural Cf/Al composites with the volume fraction of 50%,of which the reinforced material was M40 Jcarbon fiber,and the matrix alloy was ZL301.The microstructure and tensile properties in warp direction of the composites at room temperature and high temperature were investigated,and tensile failure mechanism was analyzed.The results show that at room temperature,350℃and 400℃,the tensile strength in warp direction of the composite is 650.2 MPa,619.8 MPa and 540 MPa,respectively,and the tensile modulus in warp direction is 81.78 GPa,72.76 GPa and 60.82 GPa,respectively.The tensile strength loss rates of laminated puncture structural Cf/Al composites in warp direction at 350℃and 400℃reach 4.8%and 16.95%,respectively,and the tensile modulus loss rates of laminated puncture structural Cf/Al composites in warp direction at 350℃and 400℃reach 11%and 25.67%,respectively.The tensile mechanical properties of laminated puncture structural Cf/Al composites in warp direction are decreased significantly at 350℃~400℃than that of ones at room temperature~350℃,and its displacementload curve is characterized by nonlinear.The tensile failure of laminated puncture structural Cf/Al composites in warp direction at high temperature can be divided into four stages,that is integral deformation resistance stage,accumulation stage,fracture failure stage and instability fracture stage.