(b) UIS- 380Ma PLs -350MPa PLS 250~20MPa 200 150 000000 0.1 Tensile strain(%) Tensile strain(%) 450S w410MPa UTS UTS R400}~360MPa w 320MPa E 350 PLS 350MP P 3250~180MPa 兰 02 Tensile strain(%) Tensile strain (%) Tensile strain ( %) Fig 4. Typical stress-strain curves of SiC/Sic composites with low-V(a)at 1800C and (b)at 1900C and with high-V(c)at 1800C. (d) at 1850"C and (e)at 1900C Our 10um Fig. 5. Fracture surfaces of the Sic/Sic composites after monotonic tensile tests: (a) with low-V, at 1800C. (b)with high-V/ at 1800C and (c)with high-V, at 1900.C. 4. Conclusions sification became restricted because the fibers retarded infiltration of SiC nano-powders at lower fabrication temperature of 1800C. Densification, microstructure and mechanical properties of Sic/ Increasing of fabrication temperature dramatically enhanced the SiC composites by nano-powder infiltration and transient eutectic- infiltration and densification of Sic nano-powder in the intra-fl phase(NITE) process were highly dependent on fiber volume frac- ber-bundles and simultaneously strengthened the interaction be- tion incorporating fabrication temperature. In the composites with tween Pyc interface and matrix. Even under harsh fabrication low fiber volume fraction, densification was well achieved even at temperature of 1900C, the fibers were well protected by in- lower fabrication temperature of 1800C and then saturated at the duced-PyC coating and well-consolidation with sufficient infiltra- 3rd stage of matrix densification corresponding to classic liquid tion of Sic nano-powder in the intra-fiber-bundle. For the phase sintering In the composites with high volume fraction, den- composite with high fiber volume fraction, that could contribute4. Conclusions Densification, microstructure and mechanical properties of SiC/ SiC composites by nano-powder infiltration and transient eutectic￾phase (NITE) process were highly dependent on fiber volume frac￾tion incorporating fabrication temperature. In the composites with low fiber volume fraction, densification was well achieved even at lower fabrication temperature of 1800 C and then saturated at the 3rd stage of matrix densification corresponding to classic liquid phase sintering. In the composites with high volume fraction, den￾sification became restricted because the fibers retarded infiltration of SiC nano-powders at lower fabrication temperature of 1800 C. Increasing of fabrication temperature dramatically enhanced the infiltration and densification of SiC nano-powder in the intra-fi- ber-bundles and simultaneously strengthened the interaction be￾tween PyC interface and matrix. Even under harsh fabrication temperature of 1900 C, the fibers were well protected by in￾duced-PyC coating and well-consolidation with sufficient infiltra￾tion of SiC nano-powder in the intra-fiber-bundle. For the composite with high fiber volume fraction, that could contribute Fig. 4. Typical stress–strain curves of SiC/SiC composites with low-Vf: (a) at 1800 C and (b) at 1900 C and with high-Vf; (c) at 1800 C, (d) at 1850 C and (e) at 1900 C. Fig. 5. Fracture surfaces of the SiC/SiC composites after monotonic tensile tests: (a) with low-Vf at 1800 C, (b) with high-Vf at 1800 C and (c) with high-Vf at 1900 C. K. Shimoda et al. / Composites Science and Technology 69 (2009) 1623–1628 1627