Ceramic materials are inherently characterized by high melting points and brittleness, which pose manufacturing challenges in diverse applications. Kinetic spray methods, such as Cold Spray (CS) and Aerosol Deposition (AD), have emerged as promising techniques for depositing coatings without significant chemical reactions or phase transformations. However, it has been established that native oxide layers impede metallurgical bonding in kinetic spraying of metallic materials. Due to inherent challenges and the limited research on brittle ceramic particles, a consensus on the impact of oxide layers on ceramic coating bonding remains elusive. In this study, agglomerated GaN powders, featuring primary particle sizes of tens of nanometers and agglomerate diameters of several microns, were used to successfully fabricate nanoporous GaN coatings on stainless steel substrates via Low-Pressure Cold Spray (LPCS). During high-velocity particle impact, native oxide films on both particles and substrates were removed, followed by the generation of a new oxide layer at the particle-substrate interface. X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM) were employed to characterize interface oxidation, clarifying chemical stability and oxidation types. Local heteroepitaxy near the interface, associated with newly formed gallium oxide, promoted coating formation. The GaN coatings exhibited boundary amorphization and high dislocation density, attributed to high strain rates during particle impact. Thus, bonding mechanisms between nitride ceramic particles and stainless steel substrates can be attributed to newly formed interfacial oxidation and boundary amorphization. To mitigate environmental interactions, the Aerosol Deposition (AD) technique was also explored as an alternative kinetic spraying method for GaN coatings. Preliminary results indicate that successful GaN deposition through AD significantly depends on optimized process parameters, particularly those achieving high particle velocities. Consequently, dense and crack-free GaN layers were successfully fabricated at room temperature using helium as the process gas. Ongoing studies aim to investigate internal interfaces and clarify underlying bonding mechanisms. In conclusion, this research demonstrates the feasibility and effectiveness of kinetic spray methods for fabricating GaN coatings. The insights gained not only validate this novel approach for GaN deposition but also provide valuable guidance for kinetic spraying of a broader range of ceramic materials.

周邵云，1996 年生于甘肃兰州，工学博士（2022年9月-日本东北大学）。自2022年10月起，她在名古屋大学担任特任助教，主要研究方向涵盖陶瓷冷喷涂、气溶胶喷涂、飞秒激光加工、异种材料连接及多孔金属等。近年来，主持并承担多项重要科研项目，包括日本学术振兴会（JSPS）青年科学家基金、丰田学者计划、爱普生研究助成金、日本铝协会研究助成金，以及日本科学技术振兴机构（JST）次世代研究支援。荣获日本精细陶瓷协会2023年度森村丰明鼓励奖。申请/公开日本发明专利1项，中国发明专利3项。