| Continuous SiC fiber reinforced titanium-based composites have been applied widely to aerospace industry due to their prominent intensity, toughness, rigidity and strength of resisting creep at 600~800°C . SiC/Ti-15-3 composites are composed of high-strength SiC fibers and Ti-15-3 matrix. Because of a significant mismatch between the thermal expansions coefficients of the silicon carbide fiber and the matrix, thermally induced the interfacial thermal residual strains and stresses in SiC/Ti-15-3 composites can be significant. These thermal residual stresses (TRS) play a very important role in the mechanical properties and structure properties of the metal-matrix composites. Increase of TRS can induce microcosmic damage in the metal-matrix composites and lead to a lot of initial cracks, which cause the composites structure to break, therefore interfacial TRS has attracted much scientific interest. In our earlier work, residual stress field in interface in a single fiber was studied.Distribution of TRS in the interfacial area of SiC/Ti-15-3 composites was due to the difference between the thermal expansions coefficients of the fiber and the matrix, and their factures technique, and the location of neighbor fiber. Because the size of fibers is usually at microns order, interfacial TRS is measured only by experimental technique with high spatial resolution. Micro-moiréinterferometry is used to measure deformation and strains by high-frequency diffraction gratings and laser interferential technique. it is a modern photo-mechanics experimental method with high sensitivity, excellent contrast, full-field analysis and high spatial resolution. This research studies the distribution of TRS between the adjacent fibers using micro-moiréinterferometry method and push-out test, then this process has been numerically simulated using the finite element software, interactional influence of interfacial TRS in SiC/Ti-15-3 composites is analyzed.
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