Raman spectroscopy was utilized to characterize the chemical composition and residual stresses formed in melt infiltrated SiC/SiC CMCs during processing. Stresses in SiC fibers, in SiC chemical vapor (CVI) infiltrated matrix, in SiC melt infiltrated matrix, and in free silicon were measured for two different plates of CMCs. Stresses in the free silicon averaged around 2 GPa in compression, while stresses in the matrix SiC were 1.45 GPa in tension. The SiC CVI phase had stresses ranging between 0.9 GPa and 1.2 GPa in tension and the SiC fibers experienced stresses of .05–0.7 GPa in tension. These results were validated with the proposed model of the system. While the mismatch in the coefficients of thermal expansion between the constituents contributes to the overall residual stress state, the silicon expansion upon solidification was found to be the major contributor to residual stresses within the composite.

拉曼光谱法用于表征在加工过程中在熔渗的SiC / SiC CMC中形成的化学成分和残余应力。对于两个不同的CMC板，测量了SiC纤维，SiC化学蒸气（CVI）渗透基体，SiC熔体渗透基体和游离硅中的应力。游离硅中的应力在压缩时平均约为2 GPa，而基体SiC中的应力在拉伸时为1.45 GPa。SiC CVI相的拉应力范围为0.9 GPa至1.2 GPa，而SiC纤维的拉应力范围为.05–0.7 GPa。这些结果已通过系统提出的模型进行了验证。虽然组件之间的热膨胀系数不匹配会导致整体残余应力状态，