592 ican Ceramic societ Seo et ai whiskers that were deflected at angles of 125 and 70. were w.S Seo, C.H. Pai, K. Koumoto, and H. Yanagida, "Microstructure Develop- omposed of type A and type B whiskers, and two types of type a ment and stacking Fault Annihilation in p-Sic Powder Compact, "JCeramSoc. whiskers, respectively, depending on the di e in the growth rate loW.-S. Seo and K. Koumoto, "Kinetics and Mechanism of Stacking ault whisker had one leg and two heads, and their angles between the leg 164-0m153 Grain Growth in Porous Ceramics of B-sic,"JMater Res,8, and the stacking-fault content of each type of whisker. The Y-shaped and the heads were both 125.3 the angle between the two heads was L. Wang, H. Wada, and L. F. Allard hesis and Characterization of Sic 109.5. The growth of Y-shaped whisker was accomplished by a 12W.-S. Seo and K. Koumoto, "Stacking Faults in B-SiC Formed during Carbo- parallel growth of two pairs of type A and type B whiskers thermal Reduction of SiO2, ". An. Ceram Soc., 79[7] 1777-82(1996 W-S. Seo. K. Koumoto, and S. Arai. "Effects SiC Particles in the System SiOx-C-H2, J. Am. Ceram Soc, 81[5] 1255-61(1998). S M. Pickard and B. Derby,"TEM Study of Silicon Carbide Whisker Micro- G. Sasaki, K. Hiraga, M. Hirabayashi, K. Nihara, and T. Hirai, "Microstructure sV. V Pujar and J D Cawley, "Effect of Stacking Faults on the X-ray Diffraction Around Indentation of CVD-SiC Observed by Transmission Electron Microscopy, Yokyo Kyokaish, 94, 779-83(1986) V. D Krstic,"Production of Fine, High-Purity Beta Silicon Carbide Powders, Y.C. Zhou and F. Xia, "Effect of Processing Temperature on the Morphology of J Am Ceram Soc., 75 [1170-74(1992 G. C. Wei"Beta SiC Powders Produced by Carbothermic Reduction of Silica in P. F. Becher, C -H. Hsueh, P. Angelini, and T. N. Tiegs, ""Toughening Behavi a High-Temperature Rotary Furnace,J. Am. Ceran. Soc., 66[7 C-111-C-113 hisker-Reinforced Ceramic Matrix Composites, "J. A Ceram Soc., 71 I 1050-61(1988) M. Saito, S. Nagashima, and A. Kato, "Crystal Growth of Sic whisker from the J J. Comer, "A Study of Contrast Bands in B-siC Whiskers, Mater. Res. Bull. io(gHCO System,J. Mater: Sci. Lett, 11, 373-76(1992) 4,279-88(1969) L-G. Lee and 1. B. Cutler. "Formation of Silicon Carbide from Rice Hulls. " Ar SM. Singh, R. M. Dickerson, F. A Olmstead, and J. 1. Eldridge,"SiC (SCS-6)Fiber Ceram. Soc. Bul, 54[2]195-98(1975) Rm1ma2图 Curzio. M. K.F.mdrM、是 id growth model f13 by Single-Fiber push-Out Tests "5. Am. Ceram Soc. 81 (4)965-78(1998). Whiskers, " J. A Ceram Soc., 71 [3]149-56(1988)- H. Wang, Y. Berta, and G, S. Fischman, "Microstructure of Silicon S V Nair and Y L Wang,"Toughening Behavior of a Two-Dimensional Woven Whisker Synthesized by Carbothermal Reduction of Silicon Nitride,J.Am. Ceram. . Damage and R-Curve Behavior .J. Am Soc,755]1080-84(1992) sW.-S. Seo and K. Koumoto, "Stacking Fault and Growth Direction of B-Si Vapor-Grown B-S Whisker Synthesized by Carbothermal Reduction, Key Eng. Mater, 159[1601 2C. Cheng, R. J. Needs, and V. Heine, "Inter-layer Interactions and the Origin of 95-100(1999) SiC Polytypes, " J. Phys. C: Solid State Phys., 21, 1049(1988).whiskers that were deflected at angles of 125° and 70° were composed of type A and type B whiskers, and two types of type A whiskers, respectively, depending on the difference in the growth rate and the stacking-fault content of each type of whisker. The Y-shaped whisker had one leg and two heads, and their angles between the leg and the heads were both 125.3°; the angle between the two heads was 109.5°. The growth of Y-shaped whisker was accomplished by a parallel growth of two pairs of type A and type B whiskers. References 1 G. Sasaki, K. Hiraga, M. Hirabayashi, K. Nihara, and T. Hirai, “Microstructure Around Indentation of CVD-SiC Observed by Transmission Electron Microscopy,” Yokyo Kyokaishi, 94, 779–83 (1986). 2 Y.-C. Zhou and F. 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