ISSN   1004-0595

CN  62-1224/O4

高级检索

聚硅氮烷/MoS2高温自润滑涂层的制备及性能研究

Preparation and Properties of Polysilazane/MoS2 High Temperature Self-Lubricating Coatings

  • 摘要: 高温固体自润滑涂层因具有优异的摩擦学性能和极好的附着力,已被广泛应用于航空、航天等领域. 本文中采用陶瓷前驱体聚硅氮烷为粘接剂,MoS2为润滑填料制备了1种新型的宽温域减摩抗磨涂层. 系统探究了各因素对涂层摩擦学性能的影响,并利用扫描电镜(SEM)、X射线衍射(XRD)和Raman等表征分析涂层的微观组织、物相组成及磨损机理. 结果表明:聚硅氮烷/MoS2涂层不仅和基底结合力强,且在25~300 ℃较宽温域范围内具有优异的减摩抗磨性能. 其中300 ℃热处理的涂层在200 ℃、9 N及90 r/min的测试条件下具有最佳润滑性能:平均摩擦系数为0.05,磨损率为7.6×10−5 mm3/(N·m). 涂层在中高温下体现出优异的润滑和耐磨性能,这主要得益于MoS2特殊层状结构和弱的剪切应力以及高硬度无机非晶态陶瓷相SiOC的形成. 该涂层的成功制备有望为高温工况下服役的零部件表面润滑防护提供理论依据及数据支持.

     

    Abstract: High-temperature solid self-lubricating coatings have found extensive applications in aviation, aerospace and various other fields, owing to their remarkable tribological properties and adhesive characteristics. In this study, a novel wide-temperature range anti-friction and anti-wear coating in simple composition was prepared based on polysilazane, which could be converted into a high hardness inorganic amorphous ceramic phase SiOC at high temperatures as the film-forming materials with excellent interfaced bonding strength and wear resistance property, and MoS2 as the lubrication phase. The effects of various factors on the tribological properties of the coatings were systematically investigated, the microstructures, phase compositions and wear mechanism of the coating were analyzed through SEM, XRD, Raman and pencil hardness characterization. The results indicated that the polysilazane/MoS2 coatings prepared at lower heat treatment temperatures (25~300 ℃) exhibited excellent adhesion to the metal substrate. However, at high temperature (500 ℃), the mass loss of polysilanze during the ceramic conversion process led to crack formation and poor adhesion, primarily due to the substantial density increased and volume shrinkage of polysilazane during conversion to ceramics. Additionally, the coating demonstrated exceptional anti-friction and anti-wear properties over a wide-temperature range, spanning from room temperature (25 ℃) to 300 ℃. Specifically, the coating subjected to a 300 ℃ heat treatment performed optimally at 200 ℃, 9 N, and 90 r/min, with an average friction coefficient of 0.05 and a wear rate of 7.6×10−5 mm3/(N·m). This coating exhibited outstanding lubrication and wear resistance at medium-high temperatures, primarily attributed to the unique layered structure of MoS2 and its weak shear stress properties. However, as the heat treatment temperature reached 500 ℃, the average friction coefficient and wear rate of the coating increase significantly. This was mainly due to the oxidation of MoS2 in the coating to MoO3 with poor lubricating properties. Furthermore, the average friction coefficient of the coating showed a slight tendency to increase as the adhesive content in the coating increased, but the wear rate decreased with the increase in adhesive content. The coatings exhibited low friction coefficients and wear rates on a wide range of substrates, demonstrating their generalizability. Moreover, the coatings maintain low friction coefficients and wear rates under different loaded and rotation speeds. The successful development of this coating was expected to provide an experimental basis and theoretical guidance for enhancing surface lubrication protection for parts and components operating in room temperature to high temperature working conditions.

     

/

返回文章
返回