(中南大学 粉末冶金国家重点实验室,长沙 410083)
摘 要: 采用热弹塑性有限元数值模拟方法,研究了连接温度对C/C复合材料与Cu平面对接接头残余应力的影响。结果表明:最大拉应力的分布具有方向性,在连接界面法线方向上,最大拉应力出现在靠近接头界面的C/C复合材料侧,位于连接件的棱边上;在平行连接界面方向上,最大拉应力出现在靠近接头界面的Cu侧表面。最大剪切应力位于接头界面处。随着连接温度的升高,接头残余应力峰值逐渐增大,但接头残余应力的分布形态相似。对于连接界面尺寸为4 mm×4 mm的接头,在连接温度为1 000 ℃时,离接头界面1.2 mm的C/C复合材料侧最容易发生断裂。
关键字: C/C复合材料;Cu;连接温度;残余应力
(State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China)
Abstract:The effect of joining temperature on the residual stress in carbon/carbon (C/C) composites and copper plane butt joints was studied using thermal-elastic-plastic finite element method. The results show that the distribution of the maximum tensile stress has directionality. The maximal value of the tensile stress vertical to the joined surface is at the C/C composites side near the interface. However, in parallel to the joined surface, the maximal tensile stress reaches on the Cu side near the interface. The maximal shear stress is found at the interface. With the increase of the joining temperature, the maximal residual stress increases, but the residual stress distribution is similar. When the size of the interface is 4 mm×4 mm at 1 000 ℃, the fracture may occur mostly at the C/C composites side near interface at a distance of 1.2 mm from the edge.
Key words: C/C composites; copper; joining temperature; residual stress