无机材料学报 ›› 2025, Vol. 40 ›› Issue (2): 168-176.DOI: 10.15541/jim20240287 CSTR: 32189.14.10.15541/jim20240287

• 研究论文 • 上一篇    下一篇

气相渗硅法修复SiC涂层及其抗热震和烧蚀性能

侯佳琪1(), 陈睿聪1, 曾耀莹1, 周磊2, 张佳平1(), 付前刚1   

  1. 1.西北工业大学 超高温结构复合材料重点实验室, 陕西省纤维增强轻质复合材料重点实验室, 西安 710072
    2.无锡博智复合材料有限公司, 无锡 214000
  • 收稿日期:2024-06-12 修回日期:2024-07-25 出版日期:2025-02-20 网络出版日期:2024-09-02
  • 通讯作者: 张佳平, 研究员. E-mail: zhangjiaping@nwpu.edu.cn
  • 作者简介:侯佳琪(1999-), 女, 博士研究生. E-mail: houjiaqi@mail.nwpu.edu.cn
  • 基金资助:
    国家自然科学基金(52272044);航空发动机及燃气轮机基础科学中心项目(P2021-A-IV-003-001);河南省科技研发计划联合基金(225200810002);国家科技重大专项基础研究项目(J2022-VI-0011-0042)

Thermal Shock and Ablation Resistance of SiC Coating Repaired by Gaseous Silicon Infiltration

HOU Jiaqi1(), CHEN Ruicong1, ZENG Yaoying1, ZHOU Lei2, ZHANG Jiaping1(), FU Qiangang1   

  1. 1. State Key Laboratory of Ultra High Temperature Composite Materials, Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials, Northwestern Polytechnical University, Xi'an 710072, China
    2. Wuxi Bozhi Composites Co., Ltd., Wuxi 214000, China
  • Received:2024-06-12 Revised:2024-07-25 Published:2025-02-20 Online:2024-09-02
  • Contact: ZHANG Jiaping, professor. E-mail: zhangjiaping@nwpu.edu.cn
  • About author:HOU Jiaqi (1999-), female, PhD candidate. E-mail: houjiaqi@mail.nwpu.edu.cn
  • Supported by:
    National Natural Science Foundation of China(52272044);Science Center for Gas Turbine Project(P2021-A-IV-003-001);Joint Fund of Henan Province Science and Technology R&D Program(225200810002);National Science and Technology Major Project(J2022-VI-0011-0042)

摘要:

涂层的完整和致密性直接影响其性能。对于存在缺陷或者受到损伤的涂层, 报废并重新制备不仅浪费原材料, 还会延长制备周期。因此, 经济有效的解决方法是修复涂层, 以恢复其防护能力。本研究采用经济实用的气相渗硅法修复一次包埋法制备的多孔SiC涂层缺陷, 并对比研究了修复前后涂层的抗热震及烧蚀性能。结果表明, 修复后的包埋SiC涂层在室温~1773 K热震15次后, 其与基体之间结合良好, 失重率降低了97.05%。在氧乙炔火焰下烧蚀30 s后, 修复后的涂层中心烧蚀区域的碳纤维被SiO2所包覆, 未出现裸露或损伤。与修复前相比, 其质量损失率和厚度损失率分别降低了97.02%和67.99%。抗热震和烧蚀性能改善归因于修复后涂层致密度提高, 缺陷减少, 并且渗硅过程引入的单质Si在高温下更容易氧化生成SiO2, 有效愈合缺陷和阻挡氧气渗透, 从而防止了基体氧化损伤。本研究提出的新型涂层修复策略具有经济可行性, 为涂层缺陷及损伤修复和稳定服役提供了新途径。

关键词: SiC涂层, 热震, 烧蚀, 修复

Abstract:

Integrity and denseness of coatings significantly influence their performance. Scrapping and re-preparation of defective or damaged coatings not only lead to material waste but also prolong preparation time. To address the challenge of cost-effectiveness, repairing the coating to restore its protective capability is obviously essential. However, there is rare literature touched effective repairing method for porous SiC ceramic coatings. In this study, a straightforward and cost-effective gaseous silicon infiltration method was employed to repair defects in porous SiC coating prepared by pack cementation. Comparison experiments on thermal shock and ablation resistance of the coating were carried out before and after repair. Results demonstrated that the repaired coating exhibited robust adhesion to its substrate after 15 thermal cycles from room temperature to 1773 K, with a mass loss rate reduction of 97.05% in contrast to the pack cementation SiC coating. After ablation for 30 s, carbon fibers located in the center area of the repaired coating were successfully coated with SiO2, without naked exposure or damage. The mass and thickness loss rates were reduced by 97.02% and 67.99%, respectively. All above results indicated that thermal shock and ablation resistance of the repaired coating were enhanced, which can be attributed to the increased densification and the reduction of defects in the repaired coating. Therefore, silicon, introduced through gaseous silicon infiltration, is more easily oxidized at elevated temperature to form SiO2, which effectively heals defects and obstructs oxygen penetration, thereby preventing further oxidative damage to the substrate. This study provides a novel coating repair strategy with good economy and feasibility, constructs a new approach to effectively repair defects and damages of coatings, and enhances their service stability and durability.

Key words: SiC coating, thermal shock, ablation, repair

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