Quantitative Investigation of the Creep Resistance of Different SiC Fibers after Annealing at High Temperature

doi:10.15541/jim20250498

Abstract

Abstract:

SiC fibers exhibit exceptional high-temperature stability and mechanical properties, making them a crucial reinforcement in advanced ceramic matrix composites for reusable launch vehicles. The composition and microstructure of different types of SiC fibers vary significantly, which directly influence their high-temperature creep resistance. However, the underlying microstructural mechanisms by which heat treatment influences creep performance remain unclear. This work presents a comparative analysis of the creep behaviors of Shincolon-Ⅱ (F-1), KD-S (F-2) and KD-SA (F-3) SiC fibers. The results reveal that the superior creep resistance of F-3 is attributed to its near-stoichiometric composition and highly crystalline microstructure, while the better performance of F-2 compared to F-1 is mainly due to its lower content of free carbon and higher degree of structural ordering. High-temperature heat treatment in argon can generally improve their creep resistance. After heat treatment at 1900 ℃ for 1 h, the stress relaxation parameter (m) increases by more than 10 times for F-1 and F-2, and by approximately 5 times for F-3, compared to that of the as-received fibers tested at 1500 ℃. The mechanisms by which heat treatment enhances creep resistance differ for the different fibers. For F-1 and F-2, the dominant factors are grain growth and carbon graphitization, whereas for F-3, the improvement relies primarily on the stabilization of grain boundaries by Al compounds and graphitized carbon, along with structural densification. The findings of this work provide a theoretical foundation for improving the creep resistance of SiC fibers and optimizing their comprehensive mechanical performance.

Key words: SiC fiber, creep resistance, heat treatment, microstructure, ceramic matrix composite

CLC Number:

TQ343

ZHOU Xue, LIU Zhe, REN Yan, YU Jinshan, YANG Tianyue, ZHAO Zhongqian, WANG Honglei, ZHOU Xingui, GOU Yanzi. Quantitative Investigation of the Creep Resistance of Different SiC Fibers after Annealing at High Temperature[J]. Journal of Inorganic Materials, 2026, 41(7): 1011-1020.

Figures/Tables 10

Table 1 Relevant parameters of SiC fibers employed in this work

Fiber	Generation	C/Si ratio	Oxygen/ % (in mass)	Al/% (in mass)	Diameter/µm	Young's modulus/GPa	Tensile strength/GPa
F-1	Second	1.35	0.89	-	10.0	301	3.6
F-2	Third	1.08	0.91	-	9.9	367	3.6
F-3	Third	1.01	0.07	<1.00	9.8	373	1.7

Fig. 1 Tensile strength and tensile strength retention of SiC fibers after heat treatment at different temperatures for 1 h

Fig. 2 (a-c) Variation of stress relaxation parameter (m) with BSR testing temperature for (a) F-1, (b) F-2 and (c) F-3 fibers after being annealed at different temperatures for 1 h; (d-f) Comparison of m values of (d) as-received three SiC fibers, and the three SiC fibers after heat treatment at (e) 1600 and (f) 1900 ℃ for 1 h

Fig. 3 XRD patterns of SiC fibers after being annealed at different temperatures for 1 h

Fig. 4 (a-c) Raman spectra of (a) F-1, (b) F-2 and (c) F-3 fibers after being annealed at different temperatures; (d) ID/IG values

Fig. 5 SEM images of surfaces of (a-d) F-1, (e-h) F-2 and (i-l) F-3 fibers before and after heat treatment at 1900 ℃ for 1 h

Fig. 6 SEM images of cross-sections of (a-d) F-1, (e-h) F-2 and (i-l) F-3 fibers before and after heat treatment at 1900 ℃ for 1 h

Fig. 7 HRTEM images of (a, d) F-1, (b, e) F-2 and (c, f) F-3 fibers (a-c) before and (d-f) after heat treatment at 1900 ℃ for 1 h

Table S1 Growth rates of m values for heat-treated SiC fibers relative to as-received fibers after BSR test at different temperatures

Fiber	Heat treatment temperature/℃	Growth rate of m value after BSR test/%
Fiber	Heat treatment temperature/℃	1100 ℃	1200 ℃	1300 ℃	1400 ℃	1500 ℃
F-1	1200	2.2	2.2	11.7	8.9	17.1
	1400	5.8	16.9	68.5	62.5	68.6
	1600	12.4	30.0	131.8	467.9	1102.9
	1800	17.3	40.4	162.3	604.5	1508.6
	1900	17.7	41.3	164.2	614.3	1677.1
F-2	1200	1.2	1.2	2.9	14.4	191.1
	1400	5.1	5.0	6.4	25.2	400.0
	1600	9.6	9.7	12.2	45.6	707.1
	1800	15.9	15.5	21.1	66.7	971.4
	1900	16.7	16.3	21.9	68.8	1037.5
F-3	1200	0.1	0.6	1.7	7.6	74.2
	1400	1.8	1.5	4.3	22.2	145.4
	1600	4.1	3.6	7.7	35.5	198.8
	1800	6.9	5.9	11.7	54.0	309.8
	1900	8.8	8.7	16.5	67.3	438.0

Fig. S1 SAED patterns of (a, d) F-1, (b, e) F-2 and (c, f) F-3 fibers (a-c) before and (d-f) after heat treatment at 1900 ℃ for 1 h

References 39

[1]	IVEKOVIĆ A, NOVAK S, DRAŽIĆ G, et al. Current status and prospects of SiC_f/SiC for fusion structural applications. Journal of the European Ceramic Society, 2013, 33(10): 1577. DOI URL
[2]	PADTURE N P. Advanced structural ceramics in aerospace propulsion. Nature Materials, 2016, 15(8): 804. DOI PMID
[3]	WANG P R, LIU F Q, WANG H, et al. A review of third generation SiC fibers and SiC_f/SiC composites. Journal of Materials Science & Technology, 2019, 35(12): 2743.
[4]	KATOH Y, SNEAD L L, HENAGER C H, et al. Current status and recent research achievements in SiC/SiC composites. Journal of Nuclear Materials, 2014, 455(1/2/3): 387. DOI URL
[5]	SONG J P, JIAO J, LIU H, et al. Effect of surface state of SiC fibers on their interfacial properties. Composites Communications, 2025, 53: 102232. DOI URL
[6]	SANTORO U, NOVITSKAYA E, KARANDIKAR K, et al. Phase stability of SiC/SiC fiber reinforced composites: the effect of processing on the formation of α and β phases. Materials Letters, 2019, 241: 123. DOI URL
[7]	SHI X G, LI M Y, MA W G, et al. Experimental study on thermal transport property of KD-Ⅱ SiC fiber. Journal of Inorganic Materials, 2018, 33(7): 756. DOI URL
[8]	DONG S M, KATOH Y, KOHYAMA A. Processing optimization and mechanical evaluation of hot pressed 2D Tyranno-SA/SiC composites. Journal of the European Ceramic Society, 2003, 23(8): 1223. DOI URL
[9]	BHATT R T, HALBIG M C. Creep properties of melt infiltrated SiC/SiC composites with Sylramic™-iBN and Hi-Nicalon™-S fibers. International Journal of Applied Ceramic Technology, 2022, 19(2): 1074. DOI URL
[10]	HUGUET-GARCIA J, JANKOWIAK A, MIRO S, et al. In situ characterization of ion-irradiation enhanced creep of third generation Tyranno SA 3 SiC fibers. Journal of Materials Research, 2015, 30(9): 1572. DOI URL
[11]	HOLMES J W, PARK Y H, JONES J W. Tensile creep and creep- recovery behavior of a SiC-fiber-Si₃N₄-matrix composite. Journal of the American Ceramic Society, 1993, 76(5): 1281. DOI URL
[12]	LAMOUROUX F, VALLÉS J L, STEEN M. Uniaxial tensile and creep behaviour of an alumina fibre-reinforced ceramic matrix composite: Ⅱ. Modelling of tertiary creep. Journal of the European Ceramic Society, 1994, 14(6): 539. DOI URL
[13]	ALMANSOUR A S, MORSCHER G N. Tensile creep behavior of SiC_f/SiC ceramic matrix minicomposites. Journal of the European Ceramic Society, 2020, 40(15): 5132. DOI URL
[14]	YAJIMA S, OKAMURA K, HAYASHI J, et al. Synthesis of continuous sic fibers with high tensile strength. Journal of the American Ceramic Society, 1976, 59(7/8): 324. DOI URL
[15]	BODET R, LAMON J, JIA N Y, et al. Microstructural stability and creep behavior of Si-C-O (nicalon) fibers in carbon monoxide and argon environments. Journal of the American Ceramic Society, 1996, 79(10): 2673. DOI URL
[16]	VAHLAS C, MONTHIOUX M. On the thermal degradation of lox-M tyranno® fibres. Journal of the European Ceramic Society, 1995, 15(5): 445. DOI URL
[17]	WILSON M, OPILA E. A review of SiC fiber oxidation with a new study of Hi-Nicalon SiC fiber oxidation. Advanced Engineering Materials, 2016, 18(10): 1698. DOI URL
[18]	YOUNGBLOOD G E, LEWINSOHN C, JONES R H, et al. Tensile strength and fracture surface characterization of Hi-Nicalon™ SiC fibers. Journal of Nuclear Materials, 2001, 289(1/2): 1. DOI URL
[19]	TAKEDA M, SAEKI A, SAKAMOTO J I, et al. Effect of hydrogen atmosphere on pyrolysis of cured polycarbosilane fibers. Journal of the American Ceramic Society, 2000, 83(5): 1063. DOI URL
[20]	TAKEDA M, SAKAMOTO J, IMAI Y, et al. Properties of stoichiometric silicon carbide fiber derived from polycarbosilane// WACHTMAN J B. Proceedings of the 18th annual conference on composites and advanced ceramic materials—A:ceramic engineering and science proceedings. Hoboken: John Wiley & Sons, Inc., 1994.
[21]	BUNSELL A R, PIANT A. A review of the development of three generations of small diameter silicon carbide fibres. Journal of Materials Science, 2006, 41(3): 823. DOI URL
[22]	ISHIKAWA T, KOHTOKU Y, KUMAGAWA K, et al. High-strength alkali-resistant sintered SiC fibre stable to 2200 ℃. Nature, 1998, 391(6669): 773. DOI
[23]	GOU Y Z, WANG H, JIAN K, et al. Preparation and characterization of SiC fibers with diverse electrical resistivity through pyrolysis under reactive atmospheres. Journal of the European Ceramic Society, 2017, 37(2): 517. DOI URL
[24]	MORSCHER G N, DICARLO J A. A simple test for thermomechanical evaluation of ceramic fibers. Journal of the American Ceramic Society, 1992, 75(1): 136. DOI URL
[25]	SHA J J, PARK J S, HINOKI T, et al. Heat treatment effects on creep behavior of polycrystalline SiC fibers. Materials Characterization, 2006, 57(1): 6. DOI URL
[26]	SHA J J, PARK J S, HINOKI T, et al. Bend stress relaxation of advanced SiC-based fibers and its prediction to tensile creep. Mechanics of Materials, 2007, 39(2): 175. DOI URL
[27]	GAN Y. The regulation of microscopic composition and microstructure of KD-S silicon carbide fibers and the research on these high-temperature creep resistance. Changsha: A Master’s dissertation in National University of Defense Technology, 2018.
[28]	SHA J J, NOZAWA T, PARK J S, et al. Effect of heat treatment on the tensile strength and creep resistance of advanced SiC fibers. Journal of Nuclear Materials, 2004, 329: 592.
[29]	YUAN W, HU J B, ZHOU L, et al. Effect of argon atmosphere heat treatment on mechanical properties and microstructural evolution of Shicolon-II SiC fibers. Journal of Inorganic Materials, 2026, 41(1): 119. DOI URL
[30]	GOU Y Z, JIAN K, WANG H, et al. Fabrication of nearly stoichiometric polycrystalline SiC fibers with excellent high-temperature stability up to 1900 ℃. Journal of the American Ceramic Society, 2018, 101(5): 2050. DOI URL
[31]	WU S, GOU Y Z, XIANG Y, et al. Effect of long-time annealing at high temperature on the microstructure and mechanical properties of different types of SiC fibers. Composites Part A: Applied Science and Manufacturing, 2024, 185: 108291. DOI URL
[32]	ZHANG Y, CHEN T X, CHEN J H, et al. The effects of annealing atmosphere and intrinsic component on high temperature evolution behaviors of SiC fibers. Materials Science and Engineering: A, 2022, 848: 143363. DOI URL
[33]	WU S, GOU Y Z, WANG Y S, et al. Effect of heat treatment on composition, microstructure and mechanical property of domestic KD-SA SiC fibers. Journal of Inorganic Materials, 2023, 38(5): 569. DOI
[34]	ICHIKAWA H. Polymer-derived ceramic fibers. Annual Review of Materials Research, 2016, 46: 335. DOI URL
[35]	SHA J J, HINOKI T, KOHYAMA A. Microstructural characterization and fracture properties of SiC-based fibers annealed at elevated temperatures. Journal of Materials Science, 2007, 42(13): 5046. DOI URL
[36]	USUKAWA R, ISHIKAWA T. Effect of Al contained in polymer- derived SiC crystals on creating stable crystal grain boundaries. International Journal of Applied Ceramic Technology, 2021, 18(1): 6. DOI URL
[37]	ZHANG Y, WU C L, WANG Y D, et al. A detailed study of the microstructure and thermal stability of typical SiC fibers. Materials Characterization, 2018, 146: 91. DOI URL
[38]	ZHANG Y, CHEN J H, YAN D X, et al. Conversion of silicon carbide fibers to continuous graphene fibers by vacuum annealing. Carbon, 2021, 182: 435. DOI URL
[39]	CHEN J, ZHAO Z Q, WU S, et al. Relationship of defects and mechanical performance of high-crystalline SiC fibers after ultra-high-temperature annealing. Journal of the American Ceramic Society, 2025, 108(12): e20540.