Availableonlineatwww.sciencedirect.cor ° Science Direct CERAMICS INTERNATIONAL ELSEVIER Ceramics International 34(2008)1201-1205 www.elsevier.com/locate/ceramint Manufacturing 2D carbon-fiber-reinforced SiC matrix composites by slurry infiltration and Pip process Yunzhou Zhu, b, * Zhengren Huang a, Shaoming Dong Ming Yuan, b, Dongliang Jiang a Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, PR China School of Graduate, Chinese Academy of Sciences, Beijing 100039, PR China Received 18 December 2006: received in revised form 17 January 2007: accepted 26 February 2007 Available online 10 April 2007 Abstract ub-micrometer SiC particles were firstly added to the preceramic solution in the first infiltration step to enhance the mechanical properties 2D C SiC composites fabricated via polymer infiltration and pyrolysis(PIP)process. The effects of pyrolysis temperature and Sic-filler content on microstructures and properties of the composites were systematically studied. The results show that the failure stress and fracture toughness increased with the increase of pyrolysis temperature. SiC filler of sub-micron scale infiltrated into the composites increased the mechanical properties. As a result, for the finally fabricated composite infiltrated with a slurry containing 40 wt %o SiC filler, the failure stress was doubled ompared to that without SiC filler addition, and the fracture toughness reached 10 MPa m /2 C 2007 Elsevier Ltd and Techna Group S.r.l. All rights reserved. Keywords: B. Porosity: B Composite; C Mechanical properties; Preceramic polymer 1. Introduction degradation at elevated temperatures [9]. In recent years, with the advent of preceramic polymer with high ceramic yield Continuous fiber reinforced ceramic matrix composites polymer infiltration and pyrolysis (PIP) process has been (CFCMCs), such as CSiC, SiC Sic composites have been developed for the relatively lower processing temperature, widely recognized as the most promising candidates for brake more convenient operation and relatively simple equipment. disks, heat exchangers, advanced aero-engines, fusion power this process, the components even with complex shape and actors and space usage for their outstanding characteristics large dimension can be easily fabricated Slurry containing SiC including high toughness, low density, thermal and chemical particles is usually employed in the first infiltration step to stability, radiation tolerance and so on [1-4]. Especially, the enhance infiltration efficiency. Thus, particle content in the C SiC composites, for the relatively lower cost, larger-scale slurry should be optimized to obtain better mechanical production and better thermal stability at elevated temperature properties of C fiber, have been extensively investigated. This kind of The present research work involved the fabrication of 2D composites can be prepared by chemical vapor infiltration C SiC composites by slurry infiltration and PIP step, using (CVD), liquid or vapor silicon infiltration (LSi or VSI)and hot polycarbosilane(PCS)as preceramic precursor and Sic pressing(HP)[5-8]. CVI process is difficult to operate and particles as inert fillers. The effects of pyrolysis temperature requires complex equipment. The HP process limits the and Sic filler content on the physical and mechanical components to simple plate shapes and the consequent performances of the 2D CpSiC composites were investigated machining is of high cost. During LSI or VSI process, the residual silicon in the composite leads to material strength 2. Experimental procedure Corresponding author at: Shanghai Institute of Ceramics, Chinese Academy 2.1. Sample preparation of Sciences Shanghai 200050. PR China. Tel. +86 21 52411032 fax:+862152413903 The 2D woven C fiber fabrics(Xinka Carbon Co., Shanghai, E-mail address: yunzhouzhu@mail sic ac cn(Y Zhu). China) were used to prepare the fiber preforms which were x1 2-8842/34.00@ 2007 Elsevier Ltd and Techna Group S.r.L. All rights reserved 10.1016 1-ceramint.2007.02014
Manufacturing 2D carbon-fiber-reinforced SiC matrix composites by slurry infiltration and PIP process Yunzhou Zhu a,b, *, Zhengren Huang a , Shaoming Dong a , Ming Yuan a,b , Dongliang Jiang a a Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, PR China b School of Graduate, Chinese Academy of Sciences, Beijing 100039, PR China Received 18 December 2006; received in revised form 17 January 2007; accepted 26 February 2007 Available online 10 April 2007 Abstract Sub-micrometer SiC particles were firstly added to the preceramic solution in the first infiltration step to enhance the mechanical properties of 2D Cf/SiC composites fabricated via polymer infiltration and pyrolysis (PIP) process. The effects of pyrolysis temperature and SiC-filler content on microstructures and properties of the composites were systematically studied. The results show that the failure stress and fracture toughness increased with the increase of pyrolysis temperature. SiC filler of sub-micron scale infiltrated into the composites increased the mechanical properties. As a result, for the finally fabricated composite infiltrated with a slurry containing 40 wt.% SiC filler, the failure stress was doubled compared to that without SiC filler addition, and the fracture toughness reached 10 MPa m1/2. # 2007 Elsevier Ltd and Techna Group S.r.l. All rights reserved. Keywords: B. Porosity; B. Composite; C. Mechanical properties; Preceramic polymer 1. Introduction Continuous fiber reinforced ceramic matrix composites (CFCMCs), such as Cf/SiC, SiCf/SiC composites have been widely recognized as the most promising candidates for brake disks, heat exchangers, advanced aero-engines, fusion power reactors and space usage for their outstanding characteristics including high toughness, low density, thermal and chemical stability, radiation tolerance and so on [1–4]. Especially, the Cf/SiC composites, for the relatively lower cost, larger-scale production and better thermal stability at elevated temperature of C fiber, have been extensively investigated. This kind of composites can be prepared by chemical vapor infiltration (CVI), liquid or vapor silicon infiltration (LSI or VSI) and hot pressing (HP) [5–8]. CVI process is difficult to operate and requires complex equipment. The HP process limits the components to simple plate shapes and the consequent machining is of high cost. During LSI or VSI process, the residual silicon in the composite leads to material strength degradation at elevated temperatures [9]. In recent years, with the advent of preceramic polymer with high ceramic yield, polymer infiltration and pyrolysis (PIP) process has been developed for the relatively lower processing temperature, more convenient operation and relatively simple equipment. By this process, the components even with complex shape and large dimension can be easily fabricated. Slurry containing SiC particles is usually employed in the first infiltration step to enhance infiltration efficiency. Thus, particle content in the slurry should be optimized to obtain better mechanical properties. The present research work involved the fabrication of 2D Cf/SiC composites by slurry infiltration and PIP step, using polycarbosilane (PCS) as preceramic precursor and SiC particles as inert fillers. The effects of pyrolysis temperature and SiC filler content on the physical and mechanical performances of the 2D Cf/SiC composites were investigated. 2. Experimental procedure 2.1. Sample preparation The 2D woven C fiber fabrics (Xinka Carbon Co., Shanghai, China) were used to prepare the fiber preforms which were www.elsevier.com/locate/ceramint Ceramics International 34 (2008) 1201–1205 * Corresponding author at: Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, PR China. Tel.: +86 21 52411032; fax: +86 21 52413903. E-mail address: yunzhouzhu@mail.sic.ac.cn (Y. Zhu). 0272-8842/$34.00 # 2007 Elsevier Ltd and Techna Group S.r.l. All rights reserved. doi:10.1016/j.ceramint.2007.02.014
Y. Zhu et al. /Ceramics Intenational 34(2008)1201-1205 Table 1 Properties of the Xinka C fiber Fiber type Density (g cm) Strength(MPa) Modulus(GPa) Filament Diameter (um) Xinka 174-1.7 2000-3000 175-215 employed as reinforcement for composite fabrication in this paper. Typical properties of the fiber are listed in Table 1. The preforms were obtained by stacking the 2D 0/90 woven fabrics. The fiber volume fraction of the preform was about In the first infiltration step, slurries containing various Sic filler(0.5 um, Germany) content were used. To enhance the infiltration efficiency, the vessel containing the fiber preforms was first evacuated by a vacuum pump. Then, slurries were added to immerse the preforms and a pressure of 2 MPa was applied by gas to facilitate the infiltration process. After drying the samples were pyrolyzed at 800-1100C in nitrogen 000 1100 atmosphere with a heating rate of 5C/min. Subsequently, the pyrolyzed composites underwent seven PlP process, using Fig. 1. Open porosity as a function of pyrolysis temperature. 50 wt%(PCS)solution(with no filler 2. 2. Sample characterization strength between the matrix and fiber increased, which is more efficient in load transfer from the matrix to the fiber. However The open porosity of each sample was measured by the the measured failure stress is lower than the calculated strength Archimedes method. The flexural strength was obtained by which can be calculated by the following formula three-point-bend testing on the Instron 5566 universal testing machine, with samples of 2.5 mm x 4 mm x 36 mm dimen- oRVe ions, a cross-head speed of 0.5 mm/min and a span of 24 mm. The fracture toughness(KIc) was determined by the single o is the calculated strength of the composites, of the average edge notched beam (SENB )method, with samples of strength of the fiber and V is the fiber volume fraction, 1/2, for 2.5 mm x 5.0 mm x 36 mm dimensions, a cross-head speed the 2D CSiC composite. The calculated value is 375 MPa of 0.05 mm/min, a notch depth of 2.40 mm and a span of for the as-fabricated composites. The reason is probably that 20 mm. Five individual samples were tested at each point. The formation and propagation of the microcracks in the matrix ning electron microscope(SEMg ( a polished cross sections and fracture surfaces after the bendir result in early failure of the matrix and the reinforcing fiber in test were observed by such fiber-reinforced ceramic matrix composites. When the pyrolysis temperature increased to 1100C, the fracture tough- 3. Results and discussion ness increased to e10 MPa m /2 Because rather low fracture toughness can be expected at 800C, no test of fracture tough- 3. 1. Effect of pyrolysis temperature on the physical and ness was conducted for such a low processing temperature mechanical properties The open porosity and mechanical properties of the composites pyrolyzed at 800-1100C are plotted as functions of pyrolysis temperature in Figs. I and 2. As seen from Fig. 1, a decrease of open porosity is observed with an increase of ported in [10], the preceramic polymer would be pyrolyzed completely and closed pores in the composites opened at elevated temperature with the result that 影150 the composites may be refilled in the following infiltration steps. Hence, the open porosity gradually decreased with ncrease of the pyrolysis temperature. In Fig. 2, the composite pyrolyzed at 800C exhibited the lowest failure stress of only 97 MPa. When the pyrolysis temperature was enhanced 1100C. the failure stress increased to 232 MPa, more thar two times higher than that of composite pyrolyzed at 800C With the increase of pyrolysis temperature, the bonding Fig. 2. Failure stress and toughness as functions of pyrolysis temperature
employed as reinforcement for composite fabrication in this paper. Typical properties of the fiber are listed in Table 1. The preforms were obtained by stacking the 2D 08/908 woven fabrics. The fiber volume fraction of the preform was about 30%. In the first infiltration step, slurries containing various SiC filler (0.5 mm, Germany) content were used. To enhance the infiltration efficiency, the vessel containing the fiber preforms was first evacuated by a vacuum pump. Then, slurries were added to immerse the preforms and a pressure of 2 MPa was applied by gas to facilitate the infiltration process. After drying, the samples were pyrolyzed at 800–1100 8C in nitrogen atmosphere with a heating rate of 5 8C/min. Subsequently, the pyrolyzed composites underwent seven PIP process, using 50 wt.% (PCS) solution (with no filler). 2.2. Sample characterization The open porosity of each sample was measured by the Archimedes method. The flexural strength was obtained by three-point-bend testing on the Instron 5566 universal testing machine, with samples of 2.5 mm 4 mm 36 mm dimensions, a cross-head speed of 0.5 mm/min and a span of 24 mm. The fracture toughness (KIC) was determined by the single edge notched beam (SENB) method, with samples of 2.5 mm 5.0 mm 36 mm dimensions, a cross-head speed of 0.05 mm/min, a notch depth of 2.40 mm and a span of 20 mm. Five individual samples were tested at each point. The polished cross sections and fracture surfaces after the bending test were observed by scanning electron microscope (SEM). 3. Results and discussion 3.1. Effect of pyrolysis temperature on the physical and mechanical properties The open porosity and mechanical properties of the composites pyrolyzed at 800–1100 8C are plotted as functions of pyrolysis temperature in Figs. 1 and 2. As seen from Fig. 1, a decrease of open porosity is observed with an increase of pyrolysis temperature. As reported in [10], the preceramic polymer would be pyrolyzed completely and closed pores in the composites opened at elevated temperature with the result that the composites may be refilled in the following infiltration steps. Hence, the open porosity gradually decreased with increase of the pyrolysis temperature. In Fig. 2, the composite pyrolyzed at 800 8C exhibited the lowest failure stress of only 97 MPa. When the pyrolysis temperature was enhanced to 1100 8C, the failure stress increased to 232 MPa, more than two times higher than that of composite pyrolyzed at 800 8C. With the increase of pyrolysis temperature, the bonding strength between the matrix and fiber increased, which is more efficient in load transfer from the matrix to the fiber. However, the measured failure stress is lower than the calculated strength which can be calculated by the following formula: s sR f Vf 2 s is the calculated strength of the composites, sR f the average strength of the fiber and Vf is the fiber volume fraction, 1/2, for the 2D Cf/SiC composite. The calculated value is 375 MPa for the as-fabricated composites. The reason is probably that formation and propagation of the microcracks in the matrix result in early failure of the matrix and the reinforcing fiber in such fiber-reinforced ceramic matrix composites. When the pyrolysis temperature increased to 1100 8C, the fracture toughness increased to 10 MPa m1/2. Because rather low fracture toughness can be expected at 800 8C, no test of fracture toughness was conducted for such a low processing temperature. Table 1 Properties of the Xinka C fiber Fiber type Density (g cm3 ) Strength (MPa) Modulus (GPa) Filament Diameter (mm) Xinka 1.74–1.77 2000–3000 175–215 1k 5 Fig. 1. Open porosity as a function of pyrolysis temperature. Fig. 2. Failure stress and toughness as functions of pyrolysis temperature. 1202 Y. Zhu et al. / Ceramics International 34 (2008) 1201–1205
Y. Zhu et al. /Ceramics International 34(2008)1201-1205 SiC content 40% nten 8150 SiC filler content (% 0.00.1020.3040.5060.70.8 Fig. 3. Open porosity and failure stress as functions of slurry concentration Displacement(mm) Fig. 5. Stress-displacement curves of the composites pyrolyzed at 1100C 3. 2. Effect of slurry concentration on the physical and feature suggested that high filler loading might have a negative mechanical properties influence, impeding further densification [11]. Therefore, it was considered that the effect of the filler loading on the physical The effect of SiC filler content on the open porosity and and mechanical properties should be clarified in order to failure stress of the composites was also investigated in this optimize the infiltration process. The failure stress also paper. The results are shown in Fig 3. It can be easily seen that gradually increased with the increase of SiC content. The the open porosity decreased with an increase of filler content, infiltrated Sic particles also act as a reinforcement, which leads ndicating addition of SiC filler enhanced the infiltration to increased mechanical properties of the PIP-derived matrix efficiency for higher ceramic yield and smaller volume and more tight bonding between the matrix and the fibers shrinkage can be achieved during pyrolysis. a slight which is benificial for load transfer from the matrix to the fibers enhancement of open porosity was observed when Sic filler Thus, the failure stress of the final composite was enhanced content increased from 30 to 40 wt. which may be ascribed to Fig 4 shows the cross-sectional micrographs of the 1100C the formation of more closed pores in the composite surface, processed CrSiC composite infiltrated with 40 wt % o slurry. As which hampered the further polymer infiltration process. This shown in Fig. 4(a), some isolated large pores could be observed SEM micrograph of polished cross section of the composite infiltrated with slurry containing 40 wt %o SiC: (a) inter-bundle matrix and large pores, (b) natrix and small pores and (c)fine physical compatability between matrix and fiber
3.2. Effect of slurry concentration on the physical and mechanical properties The effect of SiC filler content on the open porosity and failure stress of the composites was also investigated in this paper. The results are shown in Fig. 3. It can be easily seen that the open porosity decreased with an increase of filler content, indicating addition of SiC filler enhanced the infiltration efficiency for higher ceramic yield and smaller volume shrinkage can be achieved during pyrolysis. A slight enhancement of open porosity was observed when SiC filler content increased from 30 to 40 wt.%, which may be ascribed to the formation of more closed pores in the composite surface, which hampered the further polymer infiltration process. This feature suggested that high filler loading might have a negative influence, impeding further densification [11]. Therefore, it was considered that the effect of the filler loading on the physical and mechanical properties should be clarified in order to optimize the infiltration process. The failure stress also gradually increased with the increase of SiC content. The infiltrated SiC particles also act as a reinforcement, which leads to increased mechanical properties of the PIP-derived matrix and more tight bonding between the matrix and the fibers, which is benificial for load transfer from the matrix to the fibers. Thus, the failure stress of the final composite was enhanced. Fig. 4 shows the cross-sectional micrographs of the 1100 8C processed Cf/SiC composite infiltrated with 40 wt.% slurry. As shown in Fig. 4(a), some isolated large pores could be observed Fig. 3. Open porosity and failure stress as functions of slurry concentration. Fig. 4. Typical SEM micrograph of polished cross section of the composite infiltrated with slurry containing 40 wt.% SiC: (a) inter-bundle matrix and large pores, (b) intra-bundle matrix and small pores and (c) fine physical compatability between matrix and fiber. Fig. 5. Stress–displacement curves of the composites pyrolyzed at 1100 8C. Y. Zhu et al. / Ceramics International 34 (2008) 1201–1205 1203
Y. Zhu et al./Ceramics intenational 34(2008)1201-1205 10um Fig. 6. SEM micrograph of fractured surface for composite pyrolyzed at 1100C:(a) sound fiber pullout and (b) fine-integrity of the fiber surface. in the inter-bundle areas even after several infiltration-pyrolysis fibers, indicating no serious damage to the fiber occured cycles, which is a commonly observed phenomenon in the PlP- during the pyrolysis process. In the PlP-derived composite derived samples for the low PIP efficiency in filling such large since the density is relatively low and the matrix is loosely inter-bundle pores In Fig. 4(b), dispersed residual pores were formed, cracks easily propagate along the weak region, which easily observed in the intra-bundle regions, which were leads to fiber debonding from the matrix and then fiber ascribed to the shrinkage of the infiltrated PCS on pyrolysis pullout and the difficulty for achieving effective polymer infiltration fter the matrix was formed in the first cycle slurry infiltration. 4. Conclusions Generally, during PlP process, the size and number of residual pores left in the inter- and intra-bundle areas would gradually 2D CSiC composites were fabricated by PlP process, using decrease when the PIP cycles proceeded and then hindered slurries containing various contents of SiC filler in the first further polymer infiltration. When the residual pores were small infiltration step. The SiC filler content has a significant enough, the viscous PCS solution could not be effectively influence on the physical and mechanical properties of the infiltrated into the consolidated body. At this time, the process composites. The maximum failure stress, fracture toughness of should be stopped. It seems difficult to achieve a fully dense the composites with particulate loading have reached matrix using the present PIP process because of the difficulty in 232 MPa and 10 MPa m", respectively. The composite penetrating the polymer into small pores that exist in the pyrolyzed at 1100C has relatively weak interface and long converted matrix. A higher magnification of the fiber boundary fiber pullout dominated the fracture surface. Further work will was shown in Fig. 4(c). Fine physical compatability between be performed on preforms with increased fiber fraction to the fibers and the matrix were achieved, for no obvious circular enhance the mechanical properties to fit the requirements for cracks were observed for the thermal mismatch of the two preparing strong and/or tough composites by the present PIP Typical stress-displacement curves derived from the bending test for the composites infiltrated with slurries Acknowledgement containing various Sic content are shown in Fig. 5. The composite infiltrated with high-concentration slurry displays not only higher failure stress but also higher elastic modulus,as We are very grateful to the 973 programme for the financial observed from the linear stage of the curves These mechanical support. properties may be attributed to the relatively densely formed matrix and tight bonding between the fibers and matrix, so that References higher failure stress and elastic modulus could be achieved [12, 13]. Stress-displacement curves for composites infiltrated [1] L.F. Cheng. Y.D. Xu, L T. Zhang, R Gao, Effect of glass sealing on the oxidation behavior of three dimensional C/SiC composites in air, Carbon with Sic filler demonstrate a peseudo-ductile fracture behavior. 390001)1127-1133 After reaching the maximum value, the load decreases [2] T Ogasawara, T Ishikawa, H Ito, N. Watanabe, Multiple cracking and gradually. This characteristic might be ascribed to loosely tensile behavior for an orthogonal 3-D woven Si-Ti-C-O fiber/Si-Ti-C- formed matrix compared to that of composites prepared by HP 3)M. Suzuki, Y. Tanaka, Y Inoue, N. Miyamoto, M. Sato, K. Goda or cvi. Even though weak interface is beneficial for fiber Uniformization of boron nitride coating thickness by continuous chemical bridging and fiber pullout. It is simultaneously detrimental for apor deposition process for interphase of SiC/SiC composites, Jpn J. strength because of the low load transfer ability from the matrix Ceram.Soc.1ll(12)(2003)865-871 to fibers through the weak interface [4]X B. He, H. Yang, Preparation of SiC fiber-reinforced SiC composites, J Mater. Process. Technol. 159(2005)135-138 fracture surface after bending test for composite infiltrated (5)SM. Dong, Y. Katoh, A.Kohyama, Preparation of SiC/SiC composites by with 40 wt %o slurry is shown in Fig. 6. The fracture surface hot pressing, using Tyranno-SA fiber as reinforcement, J Am Ceram Soc demonstrates sound fiber pullout and fine-integrity of the 86(1)(2003)26-32
in the inter-bundle areas even after several infiltration-pyrolysis cycles, which is a commonly observed phenomenon in the PIPderived samples for the low PIP efficiency in filling such large inter-bundle pores. In Fig. 4(b), dispersed residual pores were easily observed in the intra-bundle regions, which were ascribed to the shrinkage of the infiltrated PCS on pyrolysis and the difficulty for achieving effective polymer infiltration after the matrix was formed in the first cycle slurry infiltration. Generally, during PIP process, the size and number of residual pores left in the inter- and intra-bundle areas would gradually decrease when the PIP cycles proceeded and then hindered further polymer infiltration. When the residual pores were small enough, the viscous PCS solution could not be effectively infiltrated into the consolidated body. At this time, the process should be stopped. It seems difficult to achieve a fully dense matrix using the present PIP process because of the difficulty in penetrating the polymer into small pores that exist in the converted matrix. A higher magnification of the fiber boundary was shown in Fig. 4(c). Fine physical compatability between the fibers and the matrix were achieved, for no obvious circular cracks were observed for the thermal mismatch of the two phases. Typical stress–displacement curves derived from the bending test for the composites infiltrated with slurries containing various SiC content are shown in Fig. 5. The composite infiltrated with high-concentration slurry displays not only higher failure stress but also higher elastic modulus, as observed from the linear stage of the curves. These mechanical properties may be attributed to the relatively densely formed matrix and tight bonding between the fibers and matrix, so that higher failure stress and elastic modulus could be achieved [12,13]. Stress–displacement curves for composites infiltrated with SiC filler demonstrate a peseudo-ductile fracture behavior. After reaching the maximum value, the load decreases gradually. This characteristic might be ascribed to loosely formed matrix compared to that of composites prepared by HP or CVI. Even though weak interface is beneficial for fiber bridging and fiber pullout. It is simultaneously detrimental for strength because of the low load transfer ability from the matrix to fibers through the weak interface. Fracture surface after bending test for composite infiltrated with 40 wt.% slurry is shown in Fig. 6. The fracture surface demonstrates sound fiber pullout and fine-integrity of the fibers, indicating no serious damage to the fiber occured during the pyrolysis process. In the PIP-derived composite, since the density is relatively low and the matrix is loosely formed, cracks easily propagate along the weak region, which leads to fiber debonding from the matrix and then fiber pullout. 4. Conclusions 2D Cf/SiC composites were fabricated by PIP process, using slurries containing various contents of SiC filler in the first infiltration step. The SiC filler content has a significant influence on the physical and mechanical properties of the composites. The maximum failure stress, fracture toughness of the composites with particulate loading have reached 232 MPa and 10 MPa m1/2, respectively. The composite pyrolyzed at 1100 8C has relatively weak interface and long fiber pullout dominated the fracture surface. Further work will be performed on preforms with increased fiber fraction to enhance the mechanical properties to fit the requirements for preparing strong and/or tough composites by the present PIP process. Acknowledgement We are very grateful to the 973 programme for the financial support. References [1] L.F. Cheng, Y.D. Xu, L.T. Zhang, R. Gao, Effect of glass sealing on the oxidation behavior of three dimensional C/SiC composites in air, Carbon 39 (2001) 1127–1133. [2] T. Ogasawara, T. Ishikawa, H. Ito, N. Watanabe, Multiple cracking and tensile behavior for an orthogonal 3-D woven Si–Ti–C–O fiber/Si–Ti–C– O matrix composite, J. Am. Ceram. Soc. 84 (7) (2001) 1565–1574. [3] M. Suzuki, Y. Tanaka, Y. Inoue, N. Miyamoto, M. Sato, K. Goda, Uniformization of boron nitride coating thickness by continuous chemical vapor deposition process for interphase of SiC/SiC composites, Jpn. J. Ceram. Soc. 111 (12) (2003) 865–871. [4] X.B. He, H. Yang, Preparation of SiC fiber-reinforced SiC composites, J. Mater. Process. Technol. 159 (2005) 135–138. [5] S.M. Dong, Y. Katoh, A. Kohyama, Preparation of SiC/SiC composites by hot pressing, using Tyranno-SA fiber as reinforcement, J. Am. Ceram. Soc. 86 (1) (2003) 26–32. Fig. 6. SEM micrograph of fractured surface for composite pyrolyzed at 1100 8C: (a) sound fiber pullout and (b) fine-integrity of the fiber surface. 1204 Y. Zhu et al. / Ceramics International 34 (2008) 1201–1205
Y. Zhu et al. /Ceramics International 34(2008)1201-1205 6] S.M. Dong, Y Katoh, A Kohyama, Processing optimization and mechan- [10] K Jian, Z.H. Chen, Q.S. Ma, w.W.Zheng, Effect of pyrolysis processes on ical evaluation of hot pressed 2D Tyranno-SA/SiC composites, J. Eu the microstructures and mechanical properties of CfSiC composites usin Ceran.Soc.23(2003)1223-1231 polycarbosilane, Mater. Sci. Eng. A 390(2005)154-158 terphase layers on microstructure, mechanical and thermal propert of [7] T. Taguchi, N. Igawa, R. Yamada, S Jitsukawa, Effect of thick [11] M. Kotani, T. Inoue, A Kohyama, Y Katoh, K Okamura, Effect of Sic eaction-bonded SiC/SiC composites, J. Phys. Chem. Solids 66(2005) mer-derived Sic/SiC composite, Mater Sci Eng. A 357(2003)376-385 576-580 [12] F. Rebillat, J. Lamon, A. Guette, The concept of a strong interface applied [8] Y.D. Xu, L.F. Cheng, L.T. Zhang, X.w. Yin, H.F. Yin, High performance to SiC/SiC composites with a Bn interphase, Acta Mater. 48(2000)4609- 3D textile Hi-Nicalon SiC/SiC composites by chemical vapor infiltration, 4618 Ceram.Int.27(2001)565-570 [13] F. Rebillat, J. Lamon, R. Naslain, E L Curzio, M. K. Ferber, T.M. Besma 19] Z.S. Rak, A process for CpSiC composites using liquid polymer infiltra- Interfacial bond strength in SiC/C/SiC composite materials as studied by tion,J.Am. Ceram.Soc.84(10)(2001)2235-2239 single-fiber push-out tests. J Am Ceram. Soc. 81(4)(1998)965-978
[6] S.M. Dong, Y. Katoh, A. Kohyama, Processing optimization and mechanical evaluation of hot pressed 2D Tyranno-SA/SiC composites, J. Eur. Ceram. Soc. 23 (2003) 1223–1231. [7] T. Taguchi, N. Igawa, R. Yamada, S. Jitsukawa, Effect of thick SiC interphase layers on microstructure, mechanical and thermal properties of reaction-bonded SiC/SiC composites, J. Phys. Chem. Solids 66 (2005) 576–580. [8] Y.D. Xu, L.F. Cheng, L.T. Zhang, X.W. Yin, H.F. Yin, High performance 3D textile Hi-Nicalon SiC/SiC composites by chemical vapor infiltration, Ceram. Int. 27 (2001) 565–570. [9] Z.S. Rak, A process for Cf/SiC composites using liquid polymer infiltration, J. Am. Ceram. Soc. 84 (10) (2001) 2235–2239. [10] K. Jian, Z.H. Chen, Q.S. Ma, W.W. Zheng, Effect of pyrolysis processes on the microstructures and mechanical properties of Cf/SiC composites using polycarbosilane, Mater. Sci. Eng. A 390 (2005) 154–158. [11] M. Kotani, T. Inoue, A. Kohyama, Y. Katoh, K. Okamura, Effect of SiC particle dispersion on microstructure and mechanical properties of polymer-derived SiC/SiC composite, Mater. Sci. Eng. A 357 (2003) 376–385. [12] F. Rebillat, J. Lamon, A. Guette, The concept of a strong interface applied to SiC/SiC composites with a BN interphase, Acta Mater. 48 (2000) 4609– 4618. [13] F. Rebillat, J. Lamon, R. Naslain, E.L. Curzio, M.K. Ferber, T.M. Besmann, Interfacial bond strength in SiC/C/SiC composite materials as studied by single-fiber push-out tests, J. Am. Ceram. Soc. 81 (4) (1998) 965–978. Y. Zhu et al. / Ceramics International 34 (2008) 1201–1205 1205