An analysis of thermal residual stresses in SiCf/Cu composites when TiC or Ni as binder

The interfacial bonding strength of SiC fiber reinforced copper matrix composites is extremely weak. Using Ti or other metallic elements such as Fe, Ni, Mo can improve the fiber/matrix bonding strength because these elements can form carbides or an interdiffusion zone between the fiber and the matrix though a heat treatment. In this paper, a TiC reaction layer or Ni interlayer is introduced as a binder, and thermal residual stresses (TRS) in the SiC fiber, TiC or Ni interlayers, and matrix are simulated by means of finite element method. The results indicate that the matrix undergoes significant plastic deformation when the composite is cooled to room temperature from the bonding temperature, and the residual plastic strains are highest around the interlayers and decrease as distance from the interlayer increases; the values and distributions of hoop stresses and Von Mises stresses in the matrix are nearly identical when different interlayers are used , while the magnitudes of these stresses are significantly different in different kinds of interlayers. The distribution characteristics of axial residual stresses in the matrix change when different interlayers are used, and Ni is superior to TiC as the axial stresses greatly decrease near the axial end of the composite.