Journal of Inorganic Materials ›› 2024, Vol. 39 ›› Issue (6): 726-732.DOI: 10.15541/jim20230471

Special Issue: 【结构材料】超高温结构陶瓷(202409) 【结构材料】陶瓷基复合材料(202409)

• RESEARCH ARTICLE • Previous Articles     Next Articles

Microstructure and Properties of C/HfC-SiC Composites Prepared by Slurry Impregnation Assisted Precursor Infiltration Pyrolysis

SU Yi1(), SHI Yangfan1, JIA Chenglan1, CHI Pengtao2, GAO Yang2, MA Qingsong1, CHEN Sian1()   

  1. 1. Science and Technology on Advanced Ceramic Fibers &Composites Laboratory, National University of Defense Technology, Changsha 410073, China
    2. Science and Technology on Space Physics Laboratory, China Academy of Launch Vehicle Technology, Beijing 100076, China
  • Received:2023-10-13 Revised:2023-12-05 Published:2024-06-20 Online:2024-03-05
  • Contact: CHEN Sian, associate professor. E-mail: chensian07@nudt.edu.cn
  • About author:SU Yi (2000-), male, Master candidate. E-mail: suyi@nudt.edu.cn
  • Supported by:
    National Defense Science and Technology Key Laboratory Fund(6142907210301);National Key Basic Research Program(2023-JCJQ-ZD-042-00)

Abstract:

In response to the urgent demand for ultra-high temperature ceramic matrix composites with integrated thermal protection and load-bearing capabilities for high-speed aircrafts, this study prepared stable ceramic slurry from submicron HfC ceramic powder, and utilized the slurry pressure impregnation-assisted precursor infiltration pyrolysis (PIP) process to fabricate C/HfC-SiC composites with uniformly distributed HfC matrix to overcome the shortcomings of the existing reaction-derived HfC precursor, such as high cost, low efficiency, and poor densification effect. The influence of HfC content on the microstructure, mechanical properties, and ablation resistance of composites was investigated. Results showed that the composites had density of 2.20-2.58 g·cm-3 and open porosity of approximately 5% when the actual volume fraction of HfC was in range of 13.1%-20.3%. Utilizing a single layer of carbon cloth to impregnate the ceramic slurry with pressure, HfC particles were able to disperse into the interior of the fiber bundle and distributed relatively evenly in the composites. Increasing the HfC content resulted in reducted fiber content, and decreased mechanical properties of composites. Specifically, when HfC volume fraction was 20.3%, the composites exhibited density, tensile strength and fracture toughness of 2.58 g·cm-3, 147 MPa and 9.3 MPa·m1/2, respectively. Following 60 s of ablation under an oxygen acetylene flame, the composites demonstrated linear ablation rate of 0.0062 mm/s and mass ablation rate of 0.005 g/s. The molten phase HfxSiyOz formed during the ablation process could effectively cover the composites surface and provide protection.

Key words: C/HfC-SiC composite, slurry impregnation, mechanical property, ablation resistance

CLC Number: