Residual stress originated from thermal expansion mismatch determines the mechanical properties of ceramic matrix composites(CMCs).Here,continuous SiC fiber reinforced SiC matrix(SiC_(f)/SiC)composites were fabricated...Residual stress originated from thermal expansion mismatch determines the mechanical properties of ceramic matrix composites(CMCs).Here,continuous SiC fiber reinforced SiC matrix(SiC_(f)/SiC)composites were fabricated by nano-infiltration and transient eutectic-phase(NITE)method,and the residual stress of the composites was investigated using high-temperature Raman spectrometer.With temperature increasing from room temperature to 1400℃,the residual stresses of the matrix and the fiber decrease from 1.29 to 0.62 GPa and from 0.84 to 0.55 GPa in compression respectively,while that of the interphase decreases from 0.16 to 0.10 GPa in tension.The variation of residual stress shows little effect on the tensile strength of the composites,while causes a slight decrease in the tensile strain.The suppression of fiber/matrix debonding and fiber pulling-out caused by the residual stress reduction in the interphase is responsible for the decreasing tensile strain.This work can open up new alternatives for residual stress analysis in CMCs.展开更多
基金financial support of the research grant from National Natural Science Foundation of China (No.51902328)the research grant from Science and Technology Commission of Shanghai Municipality (No. 19ZR1464700)the research grant from Key Program of the Chinese Academy of Sciences (No.ZDRW-CN2017-1)
文摘Residual stress originated from thermal expansion mismatch determines the mechanical properties of ceramic matrix composites(CMCs).Here,continuous SiC fiber reinforced SiC matrix(SiC_(f)/SiC)composites were fabricated by nano-infiltration and transient eutectic-phase(NITE)method,and the residual stress of the composites was investigated using high-temperature Raman spectrometer.With temperature increasing from room temperature to 1400℃,the residual stresses of the matrix and the fiber decrease from 1.29 to 0.62 GPa and from 0.84 to 0.55 GPa in compression respectively,while that of the interphase decreases from 0.16 to 0.10 GPa in tension.The variation of residual stress shows little effect on the tensile strength of the composites,while causes a slight decrease in the tensile strain.The suppression of fiber/matrix debonding and fiber pulling-out caused by the residual stress reduction in the interphase is responsible for the decreasing tensile strain.This work can open up new alternatives for residual stress analysis in CMCs.
