J.. Haslam et al. / Journal of pean Ceramic Society 20(2000)607-618 homogenous powder matrix with a very high particle 5. Levi, C G. Yang, J Y,Dalgleish, B J, Zok, FWand Evans packing density. The use of cubic zirconia particles A. G, The processing and performance of an all-oxide ceramic allows the matrix to be strengthened by a HCl heat mposite.J.Am. Ceram. Soc., submitted February 1997 treatment that sinters and then coarsens the ZrO2 por-. Haslam, J. 3. and limite andairocessing and mechanical tion of the matrix without densification. The coarsening Properties of porous mull vaporation/condensation sintering, to be published of the zro2 grains makes the matrix resistant to further 7. Zok, F, Lange, F. Porter, F and John. R, Packing density of shrinkage in an air environment. The porous but mposite powder mixtures. J. Am. Ceram. Soc., 1991, 74(8) shrinkage resistant powder matrix provides stability to 1880-1885 e matrix that must remain porous to provide the 8. Sudre O. and Lange, F. F. The effect of inclusions on densifica- tion: Ill, the desintering phenomenon J. Am. Ceram. Soc., 1992, notch insensitivity. The addition of mullite to the matrix further stabilizes the porous microstructure.6 9. Heintz, J -M, Sudre, O. and Lange, F. F, Instability of poly Testing of the layered woven fiber composite with the ystalline bridges that span cracks in powder films densified on a fiber layers horizontal to the bending plane was used bstrate. J. m Ceram Soc, 1994. 77(3). 787-791 characterize the interlaminar shear strength of the com- 10. Tu, w. C. and Lange, F. F, Liquid precursor infiltration and posites. For this composite, there were interlaminar pyrolysis of powder compacts: Il, fracture toughness and shear failures in the matrix in between the planes of the I1. Wilson, D. M, Statistical tensile strength of Nextel 610 ane woven fibers although some anomalies were observed Nextel 720 fibres. J. Mater. Sci., 1997, 32(10). 2535-2542. The interlaminar shear strength was approximately 8 12. Wilson, D. M, Lieder, S. L. and Lueneburg. D. C,Micro- I 1 MPa. This was in the range of those measured for structure and high temperature properties of 85%0 Al2Or-15 similar composites using the same woven oxide fibers Sio2 fibers. Intermetallic Matrix Composites Il Symposium. San Francisco, CA, USA. 4-6, April 1994. ed J. A. Graves, R. R used here Iphia, PA, USA: Mater. Bending tests with the fibers oriented in-plane(verti Res Soc, 1994. pp 89-98 cally) showed that the composite had a strength of 165 13. Readey, M J. and Readey, D. W Sintering of ZrO2 in HCI MPa, which is comparable to other composites using 14. Colic, M, Franks, G, Fisher,M. and Lange, F, Chemisorption his type of woven oxide fiber. Moderate notch insensi- of organofunctional silanes or silicon nitride for improved aqu- tivity in the 0/90 fiber orientation was shown. The eous processing. J. Am. Ceram. Soc., 1998, 81(9). omposite produced here appears to have similar prop 15. Klein, S, Fisher, M. Franks. G, Colic, M. and Lange. F. erties to other porous oxide matrix composites using Comparison of the infuence on the interparticle pair potentials this type of fiber but has the advantage of (1) simple on the rheological behavior of zirconia: part B- the influence of processing method and (2)a matrix microstructure that surfactants, to be published. 16. Chang, J C, Lange, FF, Pearson, D. S and Pollinger, J. P. Pres- is resistant to densification during use sensitivity for particle packing of aqueous Al2O3 and Zro2/ Al2O3 composite slurries vs interparticle potentials: particle packing and mass segregation. J. Am. Ceram. Soc., 1991, 4(9). 2201-2204. Acknowledgements 17. Franks, G.V. Colic, M., Fisher, M. L and Lange, F. F. Plastic tobrittle transition of consolidated bodies effect of counterion size.J. Colloid Interface Sci., 1997, 193. 96-103 Research supported under AFOSR award number 18. Franks, G.V.Velamakanni, B. V and Lange, F.F. vibra- F49620-96-1-0003. The authors appreciated useful dis- cussions with Dr. Carlos Levi, Dr James Yang, and Dr mina slurries, J. Am. Ceram Soc. 78(5), 1324, 1328(1995).and Frank Zolk. Dr. Karl E. Berroth supported on sabba- 5,188,780, tical leave from Swiss Federal Laboratories for materi B V. Velamakanni and FF. Lange. Feb 23, 1993. 19. Lange, F. F, Effect of interparticle potentials on particle packing als Testing and Research(EMPA) for ceramic processing, Powders and Grains 93. A. A. Balkema Press. Rotterdam. 1993. 20. Berroth. K. E. Haslam. J. J. and Lange. F. F. Swiss Patent References number 1998 1317/98. Process for the fabrication of ceramic fiber osite material and components Also US Patent pendin 21. Haslam, J. J. and Lange, F. F. Observations on the effects of 1. Phillips, D. C, Int onding and the toughness of fiber reinforced glass and glass cs. J. Mater. Sci.. 1974 phase polycrystalline oxide fiber, to be published 9(11),1847-1854 22. Heathcote, J. A, Gong, X..Y., Yang. J, Ramamurty, U. and 2. He, M. Y. and Hutchinson. J. w. Crack deflection at ar Zok, F. w, In-plane mechanical properties of an all-oxide cera- ce between dissimilar elastic materials. Int. solids mic composite, submitted to J. A. Ceram. Soc., April, 1998. 1989,25.1053 23. Folsom, C. A Zok, F. w. and Lange, F. F, Mechanical beha- 3. Lange. Fred F. Tu. w. C. and Evans. A. G, Processing of damage-tolerant oxidation-resistant ceramic matrix composites by a precursor infiltration and pyrolysis method. Mater. Sci. 24. Lam, D. C. C. and Lange. F. F, Microstructural observations on Eng1995,A195,145-150. constrained densification of alumina powder containing a 4. Tu. w. C, Lange, Fred F. and Evans, A. G, Concept for a array of sapphire fibers. J. Am. Ceram. Soc., 1994, 77(7), 19 damage-tolerant ceramic composite with strong interfaces. J.Am 25. Berg, C.A., Tirosh, J. and Israeli, w, Analysis of shor eram.Soc,1996,79,417-424 bending of fiber reinforced composites.homogenous powder matrix with a very high particle packing density. The use of cubic zirconia particles allows the matrix to be strengthened by a HCl heat treatment that sinters and then coarsens the ZrO2 por￾tion of the matrix without densi®cation. The coarsening of the ZrO2 grains makes the matrix resistant to further shrinkage in an air environment. The porous but shrinkage resistant powder matrix provides stability to the matrix that must remain porous to provide the notch insensitivity. The addition of mullite to the matrix further stabilizes the porous microstructure.6 Testing of the layered woven ®ber composite with the ®ber layers horizontal to the bending plane was used to characterize the interlaminar shear strength of the com￾posites. For this composite, there were interlaminar shear failures in the matrix in between the planes of the woven ®bers although some anomalies were observed. The interlaminar shear strength was approximately 8± 11 MPa. This was in the range of those measured for similar composites using the same woven oxide ®bers used here. Bending tests with the ®bers oriented in-plane (verti￾cally) showed that the composite had a strength of 165 MPa, which is comparable to other composites using this type of woven oxide ®ber. Moderate notch insensi￾tivity in the 0/90 ®ber orientation was shown. The composite produced here appears to have similar prop￾erties to other porous oxide matrix composites using this type of ®ber but has the advantage of (1) simple processing method and (2) a matrix microstructure that is resistant to densi®cation during use. Acknowledgements Research supported under AFOSR award number F49620-96-1-0003. The authors appreciated useful dis￾cussions with Dr. Carlos Levi, Dr. James Yang, and Dr. Frank Zolk. Dr. Karl E. Berroth supported on sabba￾tical leave from Swiss Federal Laboratories for Materi￾als Testing and Research (EMPA). References 1. Phillips, D. C., Interfacial bonding and the toughness of carbon ®ber reinforced glass and glass-ceramics. J. Mater. Sci., 1974, 9(11), 1847±1854. 2. He, M. Y. and Hutchinson, J. W., Crack de¯ection at an inter￾face between dissimilar elastic materials. Int. J. Solids Struct., 1989, 25, 1053. 3. Lange, Fred F., Tu, W. C. and Evans, A. G., Processing of damage-tolerant oxidation-resistant ceramic matrix composites by a precursor in®ltration and pyrolysis method. Mater. Sci. Eng., 1995, A195, 145±150. 4. Tu, W. C., Lange, Fred F. and Evans, A. G., Concept for a damage-tolerant ceramic composite with strong interfaces. J. Am. Ceram. Soc., 1996, 79, 417±424. 5. Levi, C. G., Yang, J. Y., Dalgleish, B. J., Zok, F. W. and Evans, A. G., The processing and performance of an all-oxide ceramic composite. J. Am. Ceram. Soc., submitted February 1997. 6. Haslam, J. J. and Lange, F. F., Processing and mechanical Properties of porous mullite and zirconia mixtures sintered by evaporation/condensation sintering, to be published. 7. Zok, F., Lange, F., Porter, F. and John, R., Packing density of composite powder mixtures. J. Am. Ceram. Soc., 1991, 74(8), 1880±1885. 8. Sudre, O. and Lange, F. F., The e€ect of inclusions on densi®ca￾tion: III, the desintering phenomenon. J. Am. Ceram. Soc., 1992, 75(12), 3241±3251. 9. Heintz, J.-M., Sudre, O. and Lange, F. F., Instability of poly￾crystalline bridges that span cracks in powder ®lms densi®ed on a substrate. J. Am. Ceram. Soc, 1994, 77(3), 787±791. 10. Tu, W. C. and Lange, F. F., Liquid precursor in®ltration and pyrolysis of powder compacts: II, fracture toughness and strength. J. Am. Ceram. Soc., 1995, 78(12), 3283±3289. 11. Wilson, D. M., Statistical tensile strength of Nextel 610 and Nextel 720 ®bres. J. Mater. Sci., 1997, 32(10), 2535±2542. 12. Wilson, D. M., Lieder, S. L. and Lueneburg, D. C., Micro￾structure and high temperature properties of 85% Al2O3±15% SiO2 ®bers. Intermetallic Matrix Composites Ill Symposium. San Francisco, CA, USA, 4±6, April 1994. ed. J. A. Graves, R. R. Bowman, J. J., Lewandowski, Philadelphia, PA, USA: Mater. Res. Soc, 1994. pp. 89±98. 13. Readey, M. J. and Readey, D. W., Sintering of ZrO2 in HCl Atmospheres. J. Am. Ceram. Soc., 1986, 69(7), 580±582. 14. Colic, M., Franks, G., Fisher, M. and Lange, F., Chemisorption of organofunctional silanes or silicon nitride for improved aqu￾eous processing. J. Am. Ceram. Soc., 1998, 81 (9). 15. Klein, S., Fisher, M., Franks. G., Colic, M. and Lange, F., Comparison of the in¯uence on the interparticle pair potentials on the rheological behavior of zirconia: part B Ð the in¯uence of surfactants, to be published. 16. Chang, J. C., Lange, F. F., Pearson, D. S. and Pollinger, J. P., Pres￾sure sensitivity for particle packing of aqueous Al2O3 and ZrO2/ Al2O3 composite slurries vs interparticle potentials: particle packing and mass segregation. J. Am. Ceram. Soc., 1991, 4(9), 2201±2204. 17. Franks, G. V., Colic, M., Fisher, M. L. and Lange, F. F., Plastic￾to-brittle transition of consolidated bodies: e€ect of counterion size. J. Colloid Interface Sci., 1997, 193, 96±103. 18. Franks, G. V., Velamakanni, B. V. and Lange, F. F., Vibra￾forming and in-situ ¯occulation of consolidate, coagulated alu￾mina slurries, J. Am. Ceram. Soc. 78 (5), 1324,1328 (1995). and US Patent 5, 188, 780, Method for preparation of dense ceramic products, B.V. Velamakanni, and F.F. Lange, Feb.23, 1993. 19. Lange, F. F., E€ect of interparticle potentials on particle packing for ceramic processing, Powders and Grains 93. A. A. Balkema Press, Rotterdam, 1993. 20. Berroth, K. E., Haslam. J. J. and Lange, F. F., Swiss Patent number 1998 1317/98. Process for the fabrication of ceramic ®ber composite material and components. Also US Patent pending. 21. Haslam, J. J. and Lange, F. F., Observations on the e€ects of heat treatments in HCl on the ®ber bundle strength of a two￾phase polycrystalline oxide ®ber, to be published. 22. Heathcote, J. A., Gong, X.-Y., Yang, J., Ramamurty, U. and Zok, F. W., In-plane mechanical properties of an all-oxide cera￾mic composite, submitted to J. Am. Ceram. Soc., April, 1998. 23. Folsom, C. A., Zok, F. W. and Lange, F. F., Mechanical beha￾vior of a laminar ceramic/®ber-reinforced epoxy composite. J. Am, Ceram. Soc., 1992, 75(11), 2969±2975. 24. Lam, D. C. C. and Lange, F. F., Microstructural observations on constrained densi®cation of alumina powder containing a periodic array of sapphire ®bers. J. Am. Ceram. Soc., 1994, 77(7), 1976±1978. 25. Berg, C. A., Tirosh, J. and Israeli, W., Analysis of short beam bending of ®ber reinforced composites. In Composite Materials: J.J. 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