Characterization and control of the fiber-matrix interface in ceramic ...

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20 Table 5.1. Properties of some reinforcement and matrix materi.nls.a 'Tensile Young's Thermal Fiber Density strength modulus expansion diameter ( g/cm3) (MPa) (GPa) (10-6/oC) (pin) Fibers High modulus carbon High strength carbon CVD Sic monofilaments Nicalon Sic yarn AI umina Alum i na - bo r o s i 1 i c a t c: s Nextel 312 Nextel 480 Nextel 440 Boron mono filament Boron nitride Boron carbide 1.8 1.8 3.2 2.6 3.9 2.5 3.1 3.1 2.5 1.9 2.4 1900 3.760 3450 2060 1400 1550 1900 2000 2750 1380 2275 530 275 415 220 385 152 220 190 400 90 90 radial 8.0 8 axial < 0 4.8 1GO 3.1 10-15 8.5 20 5.5 11 5.5 11 5.5 11 4.7 100-200 7.5 /+. 5 Whiskers Sic whiskers VIS Sic whiskers Almi na Beryllia Boron carbide Graphite Slicon nitride 3.2 3.2 3.9 2.9 2.5 1.7 3.2 21000 8400 21000 13000 1.4000 21000 14000 840 580 430 3h5 Lr80 700 380 4.8 0.1-0.6 5.5 6 8.6 9.5 4.5 2.0 2.8 - t4atri.x glasses and ceramics Borosilicate glass 2.3 Soda-lime glass 2.5 Lithium aluminosilicate glass-ceramic 2.0 Magnes iun alumino - silicate glassceramic 2.7 Silica glass 2.3 Mu1 1 i te 2.8 Si3N4 3.2 Sic 3.2 CVD Sic 3.2 A1203 3.9 Zr02 5.7 Hf02 9.7 ZrC 6.8 B4C 2.5 TiR2 4.5 1.00 100 150 170 120 185 410 310 1200 300 140 69 2 10 490 1000 60 60 100 120 70 145 310 440 440 400 2 50 565 480 450 570 . 3.5 8.9 1.5 2.5-5.5 0.5-8.6 5.3 2.8 4.8 5.5 8.5 7.6 5.9 6.7 4.5 8.1 aRepresentative TJalues are given. There is considerable variation in the reported propercies for many of the materials
21 5,2 Mechanical Considerations The prediction of the properties and behavior of a selected composite system is a formidable challenge. A composite is a heterogeneous mixture of multiple phases with differing physical, chemical, and mechanical properties. The composite properties are derived from the properties of the constituents and the interaction that occur between the components. A simple calculation of tensile stress and strain for a composite containing continuous filament reinforcemeiit can be based on the following assumptions (24,48-52). 1. The filaments are perfectly aligned parallel to the tensile axis and surrounded by matrix, 2. Load is transferred from the matrix to the fibers by shear stresses at the interface. 3. The filaments, the matrix, and the composite are elongated equally according to Hooke’s Law. 4. The fiber reinforcement is fully bonded to the matrix, and the fibers all have the same strength, size, arid shape. 5. The stress on the components is determined by the modulus and the strain. On this basis, linear expressions for the modulus and strength of a composite material have been derived from the rule of mlxtures (53). The linear models are not as accurate as some of the more complex theories developed in recent years, but the mathematics is much less rigorous and general trends and relationships can be examined. The mechanical properties of the fiber and the matrix contribute to the final properties
Page 3: ORNL/TM-11039 Metals and Ceramics D
Page 6 and 7: Page 9.3 Composite Fabrication . .
Page 9: LIST OF TABLES Table Page 5,l. Prop
Page 12 and 13: Figure 8.3. 9.1.. 9.2. 9.3. 9.4. 9.
Page 14 and 15: Figure 10.18. 10.19. 10.20. 10. 21.
Page 17 and 18: ACKNOWLEDGMENTS The author wishes t
Page 19 and 20: CWCTERIZATION AND CONTROL OF THE FI
Page 21: 1. INTRODUCTION During the last sev
Page 24 and 25: The development of low-density, hig
Page 27 and 28: 3. FABRICATION TECHNIQUES 3.1 Intro
Page 29 and 30: 11 isostatic pressing (HIP), can be
Page 31: 13 utilizing the comparatively low-
Page 34 and 35: 16 ORN L- DWG 85- 4 i 4 18RS HEAT1
Page 37: 5. COMPOSITE DESIGN 5.1 Introductio
Page 41 and 42: 23 GRNL-DWG 88-74 26 Figure 5.1. Th
Page 43 and 44: 25 Equation (6) shows that the stre
Page 45 and 46: 27 of reinforcement. There are two
Page 47 and 48: 29 in strength. Conversely, the fib
Page 49 and 50: -I_- Table 5.2. Thermally induced a
Page 51 and 52: 33 1.2 ID 0.8 ;.r 1 e fi v 0.6 a4 Q
Page 53: 35 will affect the interface and, t
Page 56 and 57: 38 fiber-matrix bonding; thus, a fu
Page 58 and 59: 40 In the analysis of the mechanica
Page 60 and 61: 42 1.2 I .o .6 - E f aa '3 0.6 cn 3
Page 62 and 63: 44 will result in the matrix being
Page 64 and 65: I I MATRIX MATRIX Figure 7.1. Schem
Page 66 and 67: 48 F = 2a2H, where H is the hardnes
Page 68 and 69: 50 OWL-PHOTO 6866-86 i d c I 20pm F
Page 70 and 71: 52 where Af is the surface area of
Page 72 and 73: 54 Figure 7.4. Tensile and shear st
Page 74 and 75: 56 I I I / -c rc -c / . Om / / I /
Page 76 and 77: 58 ORNL-OWG 87-i 8234 F Figure 7.7.
Page 78 and 79: coating and the distribution of she
Page 80 and 81: 62 O m PHOTO 6676-87 i SIC FIBERS -
Page 83 and 84: the composite, therefore an interme
Page 85 and 86: methane as the reactant and is, thu
Page 87 and 88: 9. EXPERIMENTAL PROCEDURES 9.1 Depo
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71 furnace. The furnace is, therefo
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73 further protection. A 6.5-cm-dia
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76 of the specimen slowly decreased
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78 The programmer is also equipped
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80 graphite holders through multipl
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82 temperature by simply switching
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84 ORNk DWG 87- 4494 3 METAL LOGR A
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86 9.5 Fracture Surface Analvsis Th
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88 treated and untreated halves wer
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90 9.8.2 Tensile testinq In an init
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92 ORNL-DUG 85-11767R.2 ? ! 2 f CEN
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94 fracture of individual Nicalon f
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96 Figure 10.1. SiC-infiltrated Nic
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99 compared with the dimensions acq
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101 Table 10.3. Strength and modulu
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100 ORNL- DWG 87-1 6292 R CVI-I73 7
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BULK FIBER SAMPLE NO. 173: FIBER SU
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107 similar samples show the film o
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Figure 10.7. SEM micrographs showin
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111 Table 10.4. Thermochemical eval
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100 ORNL-DUG 87-15969R CVI- 170 75
Page 133 and 134:
115 Analysis conversion of of the m
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117 A 1 I S N 31 N I I'd I LN 3H 3
Page 137 and 138:
119 n 0 W n 9 v P n w- n v
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121 s m f c I m z - Ir 2 a 0 9 In u
Page 141 and 142:
Figure 10.14. SEM micrographs of in
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J ORNL-DWC 88-6289 z cF u) w I- z O
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127 300 I CVI-480 I I 1 0 R N L-DWG
Page 147 and 148:
io0 I I I I CVI- 172 75 - - 0 z v -
Page 149 and 150:
131 RAL 033021 RAL 033023 Figure 10
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133 include: the reaction of boron
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136 that BN coatings react with the
Page 156 and 157:
75 7 ORNL-DWG 87-48234 50 - - c5 z
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140 Table 10.9. Thermochemical eval
Page 160 and 161:
OANL-bwo 88-9025 ORNL-DWG 66-9027 I
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144 uncoated tows were 14 k 2 pm; t
Page 165 and 166:
11. DISCUSSION 11.1 Constituent Pro
Page 167 and 168:
149 The properties of CVD Sic have
Page 169 and 170:
151 11.2.1 Matrix cracking In the N
Page 171 and 172:
153 OWL-DWG 88-10677 CVI- (78 22 I
Page 173 and 174:
155 Table 11.3. Property comparison
Page 175 and 176:
157 a f ““f f- L c I Figure 11.
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159
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161 The equations demonstrate that
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163 calculations of the matrix depo
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165 In four of the samples, the fib
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167 Table 11.4. Properties of glass
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169 rare-earth magnets and coils to
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171 stress fields along the fiber i
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173 11.3.2 Tensile testinp, The use
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17 5 contraction have been ignored,
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177 the system, and when the result
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180 reduces fiber strength. The str
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182 15. R. A. J. Sambell, D. H. Bow
Page 202 and 203:
184 41. A. J. Caputo et al., "Fiber
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186 71, N. F. DOW, Study of Stresse
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188 98. M. H. Rawlins et al., "Inte
Page 208 and 209:
190 125. R. Warren and C-H. Anderss
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192 155. M. F. Doerner and W, D. Ni
Page 213 and 214:
APPENDIX A. AUGER ELECTRON SPECTROS
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APPENDIX B DETAILS OF THE FIBER-SHE
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200 Those for the fiber (primed) ar
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202 89-92. 93. 94. 95" 96. 97. 98-9
Page 222 and 223:
204 130-133. E. I. DUPONT DE NEMOUR
Page 224 and 225:
206 173. NATIONAL ACADEMY OF SCIENC
Page 226 and 227:
208 203 - 204. 20s. 206 - 207. 208.
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