Vol. 80. No enforcement, and should be layers the ceramic, metallic, or D. B. Marshall. J. J. Ratto, and F. F. Lange. "Enhanced Fracture Toughne one ceramic and one metallic. Also. it remains to be determined Layered Microcomposites of Ce-ZrO2 and Al, O3, J. Am. Ceram Soc., 74 should one type layer be thicker? Should a given type layer be ical Response and rupture mode of si cic Lamelar Composites "3. Phs, 50 distance from the reinforcement phase? A J Phillipps, W. J. Clegg, and T. W. Clyne, "The Correlation of Interfacial nd Macroscopic Toughness in SiC Laminates, "Composites, 24[2 166-76 The laminated matrix composite concept offers a number of (199),Beals and V C Nardone, "Tensile Behavior of a Niobium/Alumina interesting options for improving performance and lowering costs. For example, if the multiple interfaces within the lami- Composite Laminate, "JMater. Sci., 29,2526-30( A. Barnett,"Deposition and Mechanical Properties of Superlattice Thin is, increasing toughness, then it may be possible to use particles Fnms i posen an Pdemics prei new oys k 3. dited by M H Francombe this is shown to be possible, then appreciable reduction in composite costs would result. Particles of SiC are commercially Cerm Eng Sct. Proc, 15 (5)1110-17(19941Sing Al,O, Fibre Electrodes," Laminates by Electrophoret available in a variety of sizes for S1-2/lb compared to $300/lb for Nicalon SiC fiber. It may be that readily cleaved oxides mm一 such as the B-aluminas, magnetoplumbite, or monazite, may sion), Cocoa Beach, FL, January 14, 1993 appropriate materials for use as the reinforcement or as one C. Droillard, J. Lamon, and X. bourrat, "Strong Interface in CMCs, Condi- f the matrix layers of the Materials Research Society, VoL. 325(Boston, MA, November, 1994) burgh, PA ure and Tensile Behavior at Room Tempera- Laminated matrix composites containing fiber reinforcement re". Thesis. U and a matrix composed of alternate layers of C and SiC were IJ. E. Sheehan, "High-Temperature Coatings on Carbon Fibers and C-c Composites", pp. 223-66 in Carbon-Carbon Materials and Composites. Edited CVI process Layer thicknesses were in the range 0.01-0.5 um L. Vandenbulcke, S. Goujard, H. Tawil, and J.-C. Cavalier, "Method of and increased with distance from the fiber surface because of a Providing Antioxidation Protection for a Composite Material Containing Car- eduction of surface area as densification progressed. Nonlinear crack paths in the matrix indicated that lamination may enhance mechanical tough R. Naslain, J. Y. Rossignol, P. Hagenmuller, F. Christin, L. Heraud, and J J. Choury, "Synthesis and Properties of New Com Temperature Based on Carbon Fibers and C-SiC or C-TIC Hybrid Acknowledgments: We appreciate the guidance of Dr. Alexander Matrices, " Rew. Chim. Miner, 18, 544-64(1981). IR. P. Boisvert, " Ceramic Matrix Composites via Organometallic Precur- sors"; M.S. Thesis Rensselaer Polytechnic Institute, Troy, NY, May, 1988 ngineering students who performed most of the experimentation is ap latrix Composite Material Having Improved Toughness, "U.S References No.50079039, January7,1992. w. J. Lackey and T. L. Starr, "Fabricatio oq. 8 40130-3 ( 9g ensinicanion during cwI Processing, 3. Am. ceram. R. P. Boisvert, "A Thermodynamic and Kinetic Study of the Deposition of M.R. Piggott, Load Bearing Fibre Composites. Pergamon Press, New York, R. Goujard, L. Vandenbulcke, J. Rey, J. -L Charvet, and H. Tawil,"Process Rensselaer Polytechnic Institute, Troy, NY, December 1995 for the Manufacture of a Refractory Composite Material Protected against Cor- W. S. Stefhier and R. J. Shinayski "Toughened SiC Fiber-Reinforced Ceram- rosion, U.S. Pat No. 5246736 ics via Multiple Unbonded SiC Matrix Layers" presented at the 19th Annual onference on Composites and Advanced Ceramics, Cocoa Beach, FL, January S. Vaidyaraman, w. J. Lackey, G. B. Freeman, P. K. Agrawal, and M. D in Microlaminae Forced Flow- Thermal gradient NiCu and Fe-Cu Condensates Thin Solid Films, 72, 261-75(1980) Chemical Vapor Infiltration, "J. Mater: Res, 10[6] 1469-77(1995116 Journal of the American Ceramic Society— Lackey et al. Vol. 80, No. 1 6 D. B. Marshall, J. J. Ratto, and F. F. Lange, “Enhanced Fracture Toughness reinforcement, and should be layers the ceramic, metallic, or in Layered Microcomposites of Ce–ZrO2 and Al2O3,” J. Am. Ceram. Soc., 74 one ceramic and one metallic. Also, it remains to be determined [12] 2979–87 (1991). whether the laminate layers should be of equal thickness or 7 M. Ignat, M. Nadal, C. Bernard, M. Ducarrioir, and F. Teyssandier, “Mechan- should one type layer be thicker? Should a given type layer be ical Response and Rupture Mode of SiC/C Lamellar Composites,” J. Phys., 50, of uniform thickness, or should the layers vary in thickness with C5–259 (1989). 8 A. J. Phillipps, W. J. Clegg, and T. W. Clyne, “The Correlation of Interfacial distance from the reinforcement phase? and Macroscopic Toughness in SiC Laminates,” Composites, 24 [2] 166–76 The laminated matrix composite concept offers a number of (1993). interesting options for improving performance and lowering 9 J. T. Beals and V. C. Nardone, “Tensile Behavior of a Niobium/Alumina costs. For example, if the multiple interfaces within the lami- Composite Laminate,” J. Mater. Sci., 29, 2526–30 (1994). 10 nated matrix are effective in retarding crack propagation, that S. A. Barnett, “Deposition and Mechanical Properties of Superlattice Thin Films”; pp. 1–77 in Physics of Thin Films, Vol. 17. Edited by M. H. Francombe is, increasing toughness, then it may be possible to use particles and J. L. Vossen. Academic Press, New York, 1993. or platelets, rather than fibers, as the reinforcement phase. If 11M. Whitehead, P. Sarkar, and P. S. Nicholson, “Non-Planar Al2O3 /YPSZ this is shown to be possible, then appreciable reduction in Laminates by Electrophoretic Deposition Using Al2O3 Fibre Electrodes,” composite costs would result. Particles of SiC are commercially Ceram. Eng. Sci. Proc., 15 [5] 1110–17 (1994). 12T. Huynh and W. E. Bustamante, “Non-Oxidizing Interface (NOI) for available in a variety of sizes for $1–2/lb compared to $300/lb Ceramic Matrix Composites Processed by CVI Technique”; presented at 17th for Nicalon SiC fiber. It may be that readily cleaved oxides, Annual Conference on Composites, Materials, and Structures (Restricted Ses- such as the b9-aluminas, magnetoplumbites, or monazite, may sion), Cocoa Beach, FL, January 14, 1993. 13 be appropriate materials for use as the reinforcement or as one C. Droillard, J. Lamon, and X. Bourrat, “Strong Interface in CMCs, Condi￾of the matrix layers. tion for Efficient Multilayered Interphases”; in Proceedings of the Fall Meeting of the Materials Research Society, Vol. 325 (Boston, MA, November, 1994). Materials Research Society, Pittsburgh, PA, in press. 14C. Droillard, “2D-SiC/SiC CVI Composite with a (C-SiC) V. Summary n Multilayered Interphase: Processing, Microstructure and Tensile Behavior at Room Tempera￾Laminated matrix composites containing fiber reinforcement ture”; Thesis. University of Bordeaux, France, June, 1993. 15J. E. Sheehan, “High-Temperature Coatings on Carbon Fibers and C–C and a matrix composed of alternate layers of C and SiC were Composites”; pp. 223–66 in Carbon–Carbon Materials and Composites. Edited successfully prepared using the forced-flow–thermal-gradient by J. D. Buckley and D. D. Edie. Noyes Publications, Park Ridge, NJ, 1993. CVI process. Layer thicknesses were in the range 0.01–0.5 mm 16L. Vandenbulcke, S. Goujard, H. Tawil, and J.-C. Cavalier, “Method of and increased with distance from the fiber surface because of a Providing Antioxidation Protection for a Composite Material Containing Car￾bon, and a Material Protected Thereby,” U.S. Pat. No. 5 194 330, March 16, reduction of surface area as densification progressed. Nonlinear 1993. crack paths in the matrix indicated that lamination may enhance 17R. Naslain, J. Y. Rossignol, P. Hagenmuller, F. Christin, L. Heraud, and mechanical toughness. J. J. Choury, “Synthesis and Properties of New Composite Materials for High Temperature Applications Based on Carbon Fibers and C–SiC or C–TiC Hybrid Acknowledgments: We appreciate the guidance of Dr. Alexander Matrices,” Rev. Chim. Miner., 18, 544–64 (1981). 18 Pechenik of the Air Force Office of Scientific Research. The assistance of R. P. Boisvert, “Ceramic Matrix Composites via Organometallic Precur￾Michael Miller, Regina Richards, and seven diligent undergraduate mechanical sors”; M.S. Thesis. 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