uni-axial stress–strain response and thermal conductivity degradation of ceramic matrix composite...
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Uni-axial stress–strain response and thermal conductivity degradation of ceramic matrix composite fibre tows
by C. Tang, M. Blacklock, and D. R. Hayhurst
Proceedings AVolume 465(2109):2849-2876
September 8, 2009
©2009 by The Royal Society
Schematic drawings of: (a) a DLR-XT C/C–SiC tow and (b) a HITCO C/C tow.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Schematic diagram of a typical stress–strain curve for a uni-directional CMC tow.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Continuous cracking of matrix: (a) characteristic spacing of matrix crack, (b) matrix crack and (c) a uni-directional fibre.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Stress–strain curve of a typical uni-directional tow.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Schematic diagram of fibre pullout near a single matrix crack.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Schematic diagram showing: (a) pullout of an arbitrary fibre and (b) the decrease in fibre pullout stress in an individual fibre σpo with ω, which fails arbitrarily at ωpo, for different values of D.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Normalized pullout distance of a uni-directional tow.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Typical curve for degradation of normalized longitudinal thermal conductivity with normalized composite strain.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Segmentation of transverse heat flow in a uni-directional tow: (a) overall tow and (b) subregions.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Schematic diagram of the shear stress distribution along the fibre axis.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
(a) Schematic representation of the division of the composite tow into blocks of length equal to the matrix crack spacing w and fibres denoted by solid ellipses and (b) representation of a single
conducting block.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Schematic drawing of a fibre centre-line section, showing wake debonding.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Interfacial fibre–matrix shear stress at x=0 for the blocks that have not wake debonded.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
The effect of variation of critical shear stress, τc, on normalized transverse thermal conductivity for Weibull index g=4.5 and wake debonding air gap d= 1 μm.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
The effect of variation of Weibull distribution index, g, on normalized transverse thermal conductivity for critical shear stress for wake debonding τc= 25 MPa and wake debonding air gap
d=1 μm.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
The effect of variation of wake debonding air gap, d, on normalized transverse thermal conductivity for critical shear stress for wake debonding τc= 25 MPa and Weibull index g=4.5.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
(a) DLR-XT micrograph (Del Puglia et al.2004a, 2005) and (b) schematic showing inter-fibre micro-porosity: A1, spherical pores; A2, shrinkage debonding.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society
Schematic diagram showing a single block between two successive matrix cracks.
C. Tang et al. Proc. R. Soc. A 2009;465:2849-2876
©2009 by The Royal Society