40:1243(1992) rous ughness amplitude than Nicalon fi- 9. G Binning, C F Quate, and Ch. Gerber, Atomic bers. This difference may be attributed to force microscope, Phys Reo. Lett. 56: 930(1986) differences in processing 10. T. R. Albrecth, M.M. dovek, C Higher roughness in HI-Nicalon induces Grutter, C. F. Quate, S w.J. Kuan, C. w. Frank, and R. F. W. Pease, Imaging and modification of greater roughness-induced strains and stresses which contribute to even higher atomic force microscopy, /. Appl. Phys. 64: 1178 clamping stresses than are observed with (1988) Nicalon fibers 11. S. Alexander, L. Hellemans, O Marti, ]. Schneir, V. Elings, P.K. Hansma, M. he authors thank R A Lowden of oak ridge National Laboratory and M. N. Gross of lemented using an optica 12. H. B. Butt, K H Downing, and P K. Hansma, Im- Nicalon fibers, respectively. N. C. thunks Prof. aging the membrane protein bacteriorhodop K. K. Chawla of New Mexico Tech and J with the atomic force microscope, J, Byophys Soc Honeyman of digital Instruments for useful 58:1473(1990) discussions.This work was supported by Dr. A. 13. K. K. Chawla, Z. R. Xu, A. Hlinak, and y- w Pechenik at the Air Force Ofice of Scientific Research (#F49620-95-1-0206)and the na Alumina-Type Fibers by Atomic Force Microscopy, Proc Conf on Advances in Ceramic Matrix Com tional science foundation osites, Indianapolis, IN(A 14. S. Yajima, K. Okamura, J. Hayashi, and F. E Wawner, Synthesis of continuous SiC fiber with References high tensile strength, J. Am. Ceram. Soc. 59: 324 (1976 K.KChawla, Ceramic MatrIx Compostes, Chap- 15..Ishika Silicon carbide continuous fiber man& Hall, London, p. 291(1993) (Nicalon), in Silicon Carbide Ceramics--2, S. Somiya 2. R. A. Lowden and D. P Stinton Interface modifi and Y. Inomata, eds. Elsevier, New York, p. 81 (1991) cation in Nicalon/SiC composites, Ceram. Eng SCl. 16. E. Bischoff, M. Ruhle, O. Sbaizero, and A.G. Pro.9:705(1988) 3. R. Venkatesh and K. K. Chawla, Effect of fiber Evans, Microstructural studies of the interfac one of a SiC- fiber-reinforced lithium aluminum roughness on the pullout of alumina/gl Posites, Mater. Sci. Lett. 11: 650(190 silicate glass-ceramic, A. Ceram. Sac. 72: 741 4.YMikata and M. Taya, Stress field in a coated 17.R.I. Kerans and T AParthasarathy, Theoretical continuous fiber composite subjected to thermo- mechanical loadings, / Cump Mater. 19: 554(1985) nalysis of the fiber pullout and pushout tests, J m. Ceram.Soc.74:1585(1991) 5. Z.R.Xu, K.K. Chawla, A. Neuman, A. Wolf- 18. T. A. Parthasarathy, P D Jero, and R J. Kerans, enden, G. M. Liggett, and N. Chawla, Stiffness los and density decrease due to thermal cycling in an erties from a fiber alumina fiber/magnesium alloy composite, Mat push-out test, Scripta Met. Mater. 25: 2457(1991) Sci Eng in press(1995) 19.Y.S. Toloukian and C. Y. Ho, eds, Thermophysical 6. R. W. Goettler and K.T. Faber. Interfacial shear Properties of Matter, Vol 13, Plenum, New York, P. tresses in SiC and alumina fiber reinforced 79(1977 glasses, Comp. Sci. Tech 37: 129 (1989 20. S. Shanmugham, D. P. Stinton, F. Rebillat, A Bleier T. M. Bes 7. P. D Jero and R J Kerans, The contribution of in terfacial roughness to sliding friction of ceramic fi Liaw, Oxidation-resistant interfacial coatings fo hers in a glass matrix, Scripta Met. Mater. 24: 231 ontinuous fiber ceramic composites, Ceram. Eng cl. Proc. in press(1995) 8. PD.Warren,T]. Mackin, and A G. Evans, De. 21. Engineered Materials Handbook, Vol. 4, ASM Inter- national, Materials Park, OH (1991 push-through test for the measurement of inter- face properties in composites, Acta. Metall. Mater. Received June 1995; accepted July 1995206 N. Chawla et al. . that HI-Nicalon fibers have a higher roughness amplitude than Nicalon fi￾bers. This difference may be attributed to differences in processing. Higher roughness in HI-Nicalon induces greater roughness-induced strains and stresses which contribute to even higher clamping stresses than are observed with Nicalon fibers. The authors thank R. A. Lozuden of Oak Ridge National Laboratory and M. N. Gross of Dow Corning Co. for supplying Nicalon and Hl￾Nicalon fibers, respectively. N. C. thanks Prof. K. K. Chawla of Nezu Mexico Tech and 1. Honeyman of Digital Instruments for useful discussions. This work was supported by Dr. A. Pechenik at the Air Force Office of Scienfific Research (#F49620-95-l-0206) and the Na￾tional Science Foundation. References 1. K. K. Chawla, Ceramic Matrtx Composites, Chap￾man & Hall, London, p. 291 (1993). 2. R. A. Lowden and D. I’. Stinton, Interface modifi￾cation in Nicalon/SiC composites, Ceram. Eng. Sci. Proc. 9705 (1988). 3. R. Venkatesh and K. K. Chawla, Effect of fiber roughness on the pullout of alumina/glass com￾posites, \. Mater. Sci. Left. 11:650 (1992). 4. Y. Mikata and M. Taya, Stress field in a coated continuous fiber composite subjected to thermo￾mechanical loadings, 1. Comp. Mater. 19:554 (1985). 5. Z. R. Xu, K. K. Chawla, A. Neuman, A. Wolf￾enden, G. M. Liggett, and N. Chawla, Stiffness loss and density decrease due to thermal cycling in an alumina fiber/magnesium alloy composite, Mater. Sci. Eng. in press (1995). 6. R. W. Goettler and K. T. Faber, Interfacial shear stresses in Sic and alumina fiber reinforced glasses, Comp. Sci. Tech. 37:129 (1989). 7. I’. D. Jero and R. J, Kerans, The contribution of in￾terfacial roughness to sliding friction of ceramic fi￾bers in a glass matrix, Scrlpta Met. Mater. 242315 (1990). 8. P. D. Warren, T. J. Ma&in, and A. G. Evans, De￾sign, analysis and application of an improved push-through test for the measurement of inter￾face properties in composites, Acta. Mefall. Mater. 9 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 40:1243 (1992). G. Binning, C. F. Quate, and Ch. Gerber, Atomic force microscope, Phys Reo. Lett. 56:930 (1986). T. R. Albrecth, M. M. Dovek, C A. Lang, L. I’. Grutter, C. F. Quate, S. W. J. Kuan, C. W. Frank, and R. F. W. Pease, Imaging and modification of polymers by scanning tunneling microscopy and atomic force microscopy, I. ‘4pp/. Phys. 64:1178 (1988). S. Alexander, L. Hellemans, 0 Marti, J. Schneir, V. Elings, I’. K. Hansma, M. Longmire, and J. Gurley, An atomic-resolution atomic-force microscope im￾plemented using an optical lever, 1. Appl. Phys. 65: 164 (1989). H. B. Butt, K H. Downing, and I’. K. Hansma, Im￾aging the membrane protein bacteriorhodopsin with the atomic force microscopee, 1. Byophys. Sot. 58:1473 (1990). K. K. Chawla, 2. R. Xu, A. Hlinak, and Y.-W. Chung, Surface Roughness Characterization of Three Alumina-Type Ftbers by Atomic Force Microscopy, Proc Conf. on Advances in Ceramic Matrix Com￾posites, Indianapolis, IN (April 1993). S. Yajima, K. Okamura, J. Hayashi, and F. E. Wawner, Synthesis of continuous SIC fiber with high tensile strength, 1. Am. Gram. Sot. 59~324 (1976). T. Ishikawa, Silicon carbide continuous fiber (Nicalon), in Silicon Carbide Ceramzcs--2, S. Somiya and Y. Inomata, eds., Elsevier, New York, p. 81 (1991). E. Blschoff, M. Ruble, 0. Sbaizero, and A. G. Evans, Microstructural studies of the interface zone of a Sic-fiber-reinforced lithium aluminum silicate glass-ceramic, 1. Am. Ceram. Sot. 72:741 (1989). R. J. Kerans and 7. A. Parthasarathy, Theoretical analysis of the fiber pullout and pushout tests, 1. Am. Ceram. Sot. 74:1585 (1991). T. A. Parthasarathy, I’. D. Jero, and R. J. Kerans, Extraction of interface properties from a fiber push-out test, Scripta Met. Mater. 25:2457 (1991). Y. S. Toloukian and C. Y. Ho, eds., Thermophysical Properties of Matter, Vo1.13, Plenum, New York, p. 79 (1977). S. Shanmugham, D. I’. Stinton, F. Rebillat, A. Bleier, T. M. Besmann, E. Lara-Curzio, and P. K. Liaw, Oxidation-resistant interfacial coatings for contmuous fiber ceramic composites, Ceram. Eng. Sci. Proc. in press (1995). EngIneered Materials Handbook, Vol. 4, ASM Inter￾national, Materials Park, OH (1991). Receiued June 199.5; accepted July 1995