耐火与石灰 ›› 2019, Vol. 44 ›› Issue (4): 1-6.

• 综述 •    下一篇

C/C复合材料SiC涂层结构及抗氧化性能研究

周建光  李佳艳  郝建洁  谭毅   

  1. 大连理工大学材料科学与工程学院, 大连116024
  • 出版日期:2019-08-10 发布日期:2019-10-22

Structure and oxidation resistance of SiC coating on C/C composites

Zhou Jianguang  Li Jiayan  Hao Jianjie  Tan Yi   

  1. College of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China
  • Online:2019-08-10 Published:2019-10-22

摘要:

利用包埋法和化学气相沉积法在C/C复合材料表面制备了SiC涂层。通过X射线衍射(XRD) 、扫描电镜(SEM)及热氧化试验分析了两种方法制备的SiC涂层结构特点及对C/C复合材料在1 200 ℃静态空气中的氧化行为影响。结果表明: PC-SiC涂层由不规则多边形颗粒组成,与基体结合强度高,但反应过程中基体中的碳纤维会不同程度的被Si腐蚀,随着Al2O3添加量的增加,涂层中SiC颗粒得到细化,致密度和抗氧化性能提高。CVD-SiC涂层由球状SiC颗粒组成,结晶度差,但涂层较为致密。由于涂层是通过沉积方法制备的,因此涂层与C/C基体之间存在明显的结合界面,结合强度差,涂层氧化过程中容易发生剥落。随着沉积时间的增加,涂层厚度增加,抗氧化性能提高,但要弱于PC-SiC涂层的抗氧化能力。

关键词: SiC涂层, C/C复合材料, 微观结构, 抗氧化性能, 制备工艺

Abstract:

SiC coatings were prepared on the surface of C/C composites by pack cementation and chemical vapor deposition.The structure characteristics of SiC coatings respectively prepared by two methods and the oxidation behavior of C/C composites in static air at 1 200 ℃ were analyzed by X-ray diffraction (XRD),scanning electron microscopy (SEM) and thermal oxidation experiments.The results show that the PC-SiC coating is composed of irregular polygonal particles with high binding strength to the matrix,but the carbon fiber of the matrix will be corroded by Si to different degrees during the reaction.With the increase of Al2O3 additive content,the SiC particles in the coating will be refined,resulting in higher density and antioxidant properties.The CVD-SiC coating is composed of spherical SiC particles with poor crystablline,and the coating has high density.Since the coating is prepared by deposition,there is a clear interface between the coating and the C/C matrix,and the binding strength is poor,and the coating is easy to peel during oxidation.As the deposition time increases,the thickness of the coating increases,and the antioxidant performance increases,but it is weaker than the antioxidant capacity of the PC-SiC coating.

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