Sn-based Babbitt coatings are widely used for sliding in hydrodynamic bearings. The Babbitting of bearing surfaces is among others accomplished by casting; however, this implies some disadvantages such as segregations, or susceptibility to shrinkage defects. Thermal spraying represents a promising method to overcome these challenges. To date, no studies on Babbitt coatings deposited by means of low-pressure cold spraying (LPCS) are available in the literature. In this study, a first attempt is made to produce a Sn-Sb-Cu-based composite coating reinforced with alumina particles by means of LPCS which enables the coating of internal diameters (IDs) of cylindrical components. A tailor-made feedstock was utilized which consists of a powder mixture of Sn, Sb, Cu and alumina. The composite coating is investigated with regard to its microstructural and tribological characteristics using scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDS), x-ray diffraction (XRD), as well as dry sliding experiments. Metallographic investigations demonstrate the feasibility of depositing an alumina-reinforced Sn-Sb-Cu-based composite coating with a dense microstructure and low porosity. The composite coating mainly consists of Sn, SbSn, Cu and hexagonal CuSn. Despite a small fraction of alumina particles, the microhardness of the composite coating is primarily determined by the formation of SbSn intermetallic phases dispersed in the soft Sn-Sb-rich matrix. The composite coating possesses a coefficient of friction of 0.43 ± 0.01 and wear coefficient k of 17.27 ± 7.77 × 10 −5 mm 3 N m −1 sliding against a 100Cr6 counterbody.

中文翻译：

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冷喷涂Sn-Sb-Cu基复合涂层的显微组织和摩擦学特性

锡基巴氏合金涂层广泛用于流体动力轴承的滑动。轴承表面的巴氏合金是通过铸造完成的；然而，这意味着一些缺点，例如偏析或对收缩缺陷的敏感性。热喷涂代表了克服这些挑战的有前途的方法。迄今为止，文献中没有关于通过低压冷喷涂 (LPCS) 沉积的巴氏合金涂层的研究。在这项研究中，首次尝试通过 LPCS 生产用氧化铝颗粒增强的 Sn-Sb-Cu 基复合涂层，该涂层能够涂覆圆柱形部件的内径 (ID)。使用了一种特制的原料，它由 Sn、Sb、Cu 和氧化铝的粉末混合物组成。使用扫描电子显微镜 (SEM)、能量色散 X 射线光谱 (EDS)、X 射线衍射 (XRD) 以及干滑动实验研究复合涂层的微观结构和摩擦学特性。金相研究证明了沉积具有致密微观结构和低孔隙率的氧化铝增强 Sn-Sb-Cu 基复合涂层的可行性。复合镀层主要由Sn、SbSn、Cu和六方CuSn组成。尽管只有一小部分氧化铝颗粒，复合涂层的显微硬度主要取决于分散在软质富 Sn-Sb 基体中的 SbSn 金属间相的形成。复合涂层的摩擦系数为 0.43±0.01，磨损系数 k 为 17.27±7。