Enhancing both strength and toughness of carbon/carbon composites by heat-treated interface modification

doi:10.1016/j.jmst.2018.09.055

Abstract

Abstract:

A simple method to increase both strength and toughness of carbon/carbon (C/C) composites is presented. This method is based on the heat treatment of the pre-deposited thin carbon coating, leading to the formation of more orderly pyrolytic carbon (PyC) as a functional interlayer between fiber and matrix that could optimize the interfacial sliding strength in C/C composites. Effects of such a heat-treated PyC layers on the microstructure, tensile strength and fracture behavior of unidirectional C/C composites were investigated. Results showed that although the in-situ fiber strength was deteriorated after the introduction of interfacial layer, tensile strength of the specimen was greatly improved by 38.5% compared with pure C/C composites without any treatment. The interfacial sliding stress sharply decreased, which was interpreted from finite element analysis and verified by Raman spectra. Therefore, the fracture behavior was changed from brittle fracture to multiple-matrix cracking induced non-linear mechanical behavior. Finally, the ultimate strength can be predicted by different models according to the interfacial sliding stress. Our research would provide a meaningful way to improve both strength and toughness of C/C composites.

Key words: Carbon/carbon composites, Tensile strength, Interface, Heat treatment

Jiajia Sun, Hejun Li, Liyuan Han, Qiang Song. Enhancing both strength and toughness of carbon/carbon composites by heat-treated interface modification[J]. J. Mater. Sci. Technol., 2019, 35(3): 383-393.

Figures/Tables 18

Fig. 1. Sample preparation diagram.

Fig. 2. Cross-sectional view of the composites. (a) P-C/C, (b) HI-C/C.

Fig. 3. Typical PLM image of the composites.

Fig. 4. Morphologies of the PyC interface (a) before and (b and c) after heat treatment.

Fig. 5. Raman spectra of PyC interface (a) before and (b) after heat treatment.

Fig. 6. X-ray diffraction pattern of (a) heat-treated and (b) as-deposited carbon interface.

Table 1 Microcrystalline parameters of carbon interface.

	d₀₀₂(?)	L_c (?)	L_a (?)	g (%)
As-deposited	3.416?±?0.002	28.28?±?3.71	29.16?±?0.27	27.67?±?3.29
Heat-treated	3.381?±?0.002	62.49?±?7.70	140.00?±?7.48	69.19?±?5.81

Fig. 7. SEM observation of the fracture surface of P-C/C: (a) Low-magnification image and (b and c) Enlarged images of certain area.

Fig. 8. SEM observation of the fracture surface of HI-C/C: (a) Low-magnification image and (b-d) Enlarged images of certain area.

Fig. 9. Fracture mirror measurements of pull-out carbon fibers. Typical fractured surface observation of (a) pristine and (c) heat-treated carbon fiber and (b) Weibull plots probability of pull-out pristine carbon fibers.

Fig. 10. SEM observation of transverse matrix crack in HI-C/C composites.

Table 2 The value of referred parameters.

Parameters	Values	Reference
λ	1.34	[26]
Г_m	10?J?m^-2	[27]
E_f	280 GPa	[28]
E_m	27.1 GPa	[29]

Fig. 11. The tensile stress-displacement curve of the (a) P-C/C composites and (b) HI-C/C composites.

Fig. 12. Model cells and their mesh: example of FE cell models for the analysis of RTS in (a) P-C/C and (b) HI-C/C. Mesh used for FE calculation of RTS in micro-composites: (c) P-C/C; (d) HI-C/C.

Table 3 Parameters used in the calculation of FE analysis.

Materials		Modulus: E (GPa)		Poisson ratio	CTE (°C)
Carbon fibers [37,38]	x-direction	15	ν_xy	0.25	5.7?×?10^-6
	y-direction	15	ν_xz	0.15	5.7?×?10^-6
	Axial (z)	230	ν_yz	0.15	0.7?×?10^-6
As-deposited PyC [29,38,39]	Radial (x)	12.8	ν_xy	0.15	2.2?×?10^-5
	Tangential (y)	27.1	ν_xz	0.15	5.5?×?10^-6
	Axial (z)	27.1	ν_yz	0.3	5.5?×?10^-6
Heat-treated PyC [29,40]	Radial (x)	16.7	ν_xy	0.15	2.5?×?10^-5
	Tangential (y)	38.6	ν_xz	0.15	0
	Axial (z)	38.6	ν_yz	0.3	0
Heat-treated fibers [28,37]	x-direction	20	ν_xy	0.25	6.9?×?10^-6
	y-direction	20	ν_xz	0.15	6.9?×?10^-6
	Axial (z)	280	ν_yz	0.15	0

Fig. 13. Distribution of RTS in the P-C/C. Isometric view of (a) radial stress; (c) tangential stress and (e) axial stress. Cross-sectional view of (b) radial stress; (d) tangential stress and (f) axial stress.

Fig. 14. Distribution of RTS in the HI-C/C. Isometric view of (a) radial stress; (c) tangential stress and (e) axial stress. Cross-sectional view of (b) radial stress; (d) tangential stress and (f) axial stress.

Fig. 15. (a) Enlarged Raman spectra at G peak area. Typical Raman spectra of PyC matrix (b) P-C/C and (c) HI-C/C.

References

[1]	M. Bevilacqua, A. Babutskyi, A. Chrysanthou, Carbon 95 (2015) 861-869.
[2]	K. Kuo, S. Keswani, Combust. Sci. Technol. 42 (3-4) (1985) 145-164.
[3]	J.E. Sheehan, K.W. Buesking, B.J. Sullivan, Annu. Rev. Mater. Sci. 24(1994)19-44.
[4]	X. Wu, L.R. Radovic, Carbon 43 (2005) 333-344.
[5]	C.I. Contescu, T. Guldan, P. Wang, T.D. Burchell, Carbon 50 (2012) 3354-3366.
[6]	S.S. Tzeng, W.C. Lin, Carbon 37 (12) (1999) 2011-2019.
[7]	H. Hatta, K. Goto, S. Ikegaki, I. Kawahara, M.S. Aly-Hassan, H. Hamada, J. Eur.Ceram. Soc. 25 (4) (2005) 535-542.
[8]	H. Hatta, K. Goto, T. Aoki, Compos. Sci. Technol. 65 (15-16) (2005) 2550-2562.
[9]	H.C. Cao, E. Bischoff, O. Sbaizero, M. Riihle, A.G. Evans, D.B. Marshall, L.J. Brennan, J. Am. Chem. Soc. 73 (6) (1990) 1691-699.
[10]	H. Hiroshi, A. Tatsuji, K. Itaru, K. Yasuo, J. Compos. Mater. 38 (19) (2004)1685-1698.
[11]	M. Guellali, R. Oberacker, M.J. Hoffmann, Compos. Sci. Technol. (68) (2008)1122-1130.
[12]	J.D. Hunn, G.E.Jellison Jr., R.A. Lowden, J. Nucl. Mater. 374(2008)445-452.
[13]	B. Trouvat, X. Bourrat, R. Naslain, Extended Abstr. Prog. Carbon 97 (1997)536-537.
[14]	H. Mei, Q.L. Bai, Y.Y. Sun, H.Q. Li, H.Q. Wang, L.F. Cheng, Carbon 57 (2013)288-297.
[15]	J.J. Ren, K.Z. Li, S.Y. Zhang, X.Y. Yao, S. Tian, Mater. Design. 65 (65) (2015)174-178.
[16]	H. Mei, Q.L. Bai, T.M. Ji, H.Q. Li, L.F. Cheng, Compos. Sci. Technol. 103 (103)(2014) 94-99.
[17]	B. Reznik, D. Gerthsen, K.J. Hüttinger, Carbon 39 (2) (2001) 215-229.
[18]	A. Sadezky, H. Muckenhuber, H. Grothe, R. Niesser, U. P?schl, Carbon 43(2005) 1731-1742.
[19]	M. Pawlita, J.N. Rouzaud, S. Duber, Carbon 73 (2015) 479-490.
[20]	L.E. Jones, P.A. Thrower, Carbon 29 (2) (1991) 251-269.
[21]	D.S. Knight, W.B. White, J. Mater. Res. 4 (2) (1989) 385-393.
[22]	K. Honjo, Carbon 41 (5) (2003) 979-984.
[23]	W.A. Curtin, J. Am. Ceram. Soc. 74 (11) (1991) 2837-2845.
[24]	M.D. Thouless, A.G. Evans, Acta Metall. 36 (3) (1988) 517-522.
[25]	M. Sutcu, Acta Metall. 37 (2) (1989) 651-661.
[26]	A.C. Kimber, J.G. Keer, J. Mater. Sci. Lett. 1 (8) (1982) 353-354.
[27]	K.R. Turner, J.S. Speck, A.G. Evans, J. Am.Ceram. Soc. 78 (7) (1995)1841-1848.
[28]	F.J. Liu, H.J. Wang, L.B. Xue, L.D. Fan, Z.P. Zhu, J. Mater. Sci. 43 (12) (2008)4316-4322.
[29]	J.M. Gebert, B. Reznik, R. Piat, B. Viering, K. Weidenmann, A. Wanner, O. Deutschmann, Carbon 48 (12) (2010) 3647-3650.
[30]	Y. Tanabe, E. Yasuda, J. Mater. Sci. Lett. 10 (13) (1991) 756-759.
[31]	F.E. Heredia, S.M. Spearing, A.G. Evans, J. Am. Ceram. Soc. 75 (11) (1992)3017-3025.
[32]	F.W. Zok, Hom C.L. Sbaizero, A.G. Evans, J. Am. Ceram. Soc. 74 (1) (2010)187-193.
[33]	M. Sakai, R.C. Bradt, D.B. Fischbach, J. Mater. Sci. 21 (5) (1986)1491-1501.
[34]	T.J. Mackin, P.D. Warren, A.G. Evans, Acta Metall. 40 (6) (1992) 1251-1257.
[35]	A.G. Evans, F.W. Zok, J. Mater. Sci. 29 (15) (1994) 3857-3896.
[36]	Y. Yao, S.H. Chen, J. Appl. Mech. 80 (2) (2013) 1015.
[37]	C. Pradere, C. Sauder, Carbon (46) (2008) 1874-1884.
[38]	M. Rollin, S. Jouannigot, J. Lamon, R. Pailler, Compos. Sci. Technol. 69 (9)(2009) 1442-1444.
[39]	W. Zhang, A. Li, B. Reznik, O. Deutschmann, Z. Angew. Math. Mech. 93 (5)(2013) 338-345.
[40]	R. Piat, E. Schnack, Carbon 41 (2003) 2159-2179.
[41]	O. Frank, G. Tsoukleri, I. Riaz, K. Papagelis, J. Parthenios, et al., Nat.Commun. 2(2011) 255-257.
[42]	C.A. Taylor, M.F. Wayne, W.K.S. Chiu, Thin Solid Films 429 (2003) 190-200.