| 摘要: |
| 随着雷达探测技术的发展，对装备的隐身性能也提出越来越严苛的要求，隐身技术可显著提高军事装备及军人的生存能力，提升战斗效率，取得更大的战场控制权。传统吸波涂层的制备方法工艺复杂且效率低下，作为一种热喷涂技术，由于等离子喷涂具有工艺简单、适用范围广、可操控性和可调控性高等优点，在制备吸波涂层中得到广泛应用。材料表面状态对其性能有着重要的影响，等离子渗碳同样作为一种表面处理工艺，对提高材料表面强度、耐磨性等具有重要作用。介绍了等离子喷涂的基本原理以及送粉速率、输出功率、喷涂距离、喷涂速度等涂层制备基本工艺参数对涂层的影响。研究表明，送粉速率相同时，喷涂功率过大或过小均会导致涂层质量下降；喷涂距离过小会导致涂层与基体的结合力降低，而距离过大又会降低喷涂效率和涂层密度，合理调控等离子喷涂的工艺参数对涂层质量的好坏有着直接且重要的影响。总结了近年来等离子喷涂制备吸波涂层方面的研究成果，介绍了传统渗碳热处理技术与新型渗碳热处理技术的发展，概述了等离子渗碳的发展和现状，可知加工时间及加热温度对渗碳层的性能产生了较大影响。对以上两种表面改性技术未来的研究发展进行了展望， 为航空航天、军事装备等涉及关键零部件表面改性方面提供一定的参考价值。 |
| 关键词: 等离子喷涂 吸波涂层 等离子渗碳 |
| DOI：10.11933/j.issn.1007-9289.20230104001 |
| 分类号:TB34 |
| 基金项目: |
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| Research Status of Plasma Spraying to Prepare Coating Absorption and Plasma Carburizing Technology |
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GAO Yukui, ZHENG Xiangyuan, GONG Sijie
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College of Materials Science and Engineering, Tongji University, Shanghai 201804 , China
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| Abstract: |
| With the development of radar detection technology, the demand for the stealth performance of equipment has increased. The stealth technology can significantly enhance the survivability of military equipment and personnel, improve combat efficiency, and establish greater control on the battlefield. The traditional methods for preparing radar-absorbing coatings are complex and inefficient. Plasma spraying has gained widespread application as a thermal spraying technique in the preparation of absorbing coatings owing to its simple process, broad applicability, and high controllability. The surface condition of the materials significantly impacts their performance. Plasma carburizing, as a surface treatment process, plays a vital role in improving the surface strength and wear resistance of materials. This study introduces the basic principles of plasma spraying as well as the influence of basic coating process parameters such as powder feed rate, output power, spraying distance, and spraying speed on the quality of the coatings. Research has shown that when the powder feed rate remains constant, excessively high or low spraying power can lead to a decrease in the coating quality. An excessively short spraying distance can result in poor adhesion between the coating and the substrate, whereas an excessively long distance can reduce the spraying efficiency and coating density. Therefore, the proper control of process parameters in plasma spraying directly and significantly impacts the coating quality. Subsequently, recent research results in the preparation of radar-absorbing coatings using plasma spraying are summarized. Adjusting the plasma spraying process parameters significantly affects the absorption performance. For instance, a higher spraying power can hinder the melting and deposition of the powder, leading to increased porosity and reduced dielectric constants, that in turn affect the absorption performance. In the case of composite coatings, the content of the constituent materials can be adjusted to improve the microwave absorption performance and enhance the conductivity and impedance matching, resulting in excellent absorption and mechanical properties. Additionally, temperature plays a substantial role in microwave absorption, with certain coatings demonstrating outstanding absorption performance at elevated temperatures, presenting promising prospects for high-temperature microwave absorption applications. Furthermore, this study provides an introduction to the development of traditional carburizing heat treatment methods and new carburizing heat treatment technologies. Traditional carburizing methods involve the treatment of materials followed by quenching that creates a surface with higher hardness while maintaining a softer core, thereby enhancing the surface hardness and wear resistance. The new vacuum carburizing technology uses hydrocarbons as a carbon source to treat material surfaces at pressures below atmospheric levels, minimizing deformation and avoiding issues such as surface oxidation and decarburization. However, it still faces challenges such as long processing times and high treatment temperatures. Although high-temperature carburizing improves production efficiency, it can lead to significant grain coarsening during the carburization process, affecting the fatigue performance of the material. Plasma carburizing technology uses the principle of gas discharge to cause carbon ions to collide with the surface of the material, forming a high-quality carburized layer. During ion carburizing, neutral molecules and charged particles move directionally on the surface of the material under an electric field, resulting in a higher concentration of active carbon atoms on the surface of the material than during vacuum carburizing. This substantially enhances the carburization efficiency. As surface modification technologies continue to evolve, low-temperature plasma carburizing techniques have also achieved certain research progress. The study provides an overview of the development and current status of plasma carburizing, highlighting the substantial influence of processing time and heating temperature on the performance of the carburized layer. Plasma spraying and carburizing technologies have matured over time. However, in the future, apart from adjusting the basic spraying process parameters, exploring new control methods for the electromagnetic properties, mechanical performance, and microstructure of materials regarding plasma spraying and carburizing will better meet the increasingly stringent requirements of radar-absorbing coatings. Further understanding of the mechanisms of residual stress, grain boundaries, and dislocations in materials through plasma carburizing processes is also necessary. This study also provides prospects for the future research and development of these two surface modification technologies, offering valuable insights for industries involving critical component surface modifications, such as aerospace and military equipment. |
| Key words: plasma spraying absorbing coating plasma carburizing |
