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The 6061‑aluminum alloy is most used in marine engineering equipment. We used composite co-deposition to prepare a Cu/Co-Mo-Ce alloy coating on the aluminum alloy surface, which not only solved problems related to the ready corrosion of aluminum alloy in marine environments and the difficulty of directly preparing protective coatings but also solved problems associated with the fact that CoMo alloy form many holes by introducing the rare earth Ce. An exploration of the plating process revealed that when the concentration of the other main salts was unchanged and the concentration of Ce3+ was 0.012 mol·L−1, the Cu/Co-Mo-Ce had the flattest morphology, and the best corrosion resistance. The coatings were characterized and analyzed using SEM, EDS, XRD, and XPS. Finally, the ions deposition processes were tested via cyclic voltammetry and chronoamperometry and AC impedance. [ABSTRACT FROM AUTHOR]

Electron beam physical vapor deposition (EB-PVD) with high power axial EB guns has high deposition rates and therefore is well suited for depositing comparatively thick coatings with high throughput in mass production processes. The top sliding layer on bearing shells is a well-known use case for this technology. In low-cost manufacturing, often semi-finished products such as sheets or strips are coated, from which final products with a broad range of dimensions can be manufactured. The adaptation of related processes such as pretreatment and substrate cooling of three different semi-finished products was the focus of the investigations. All process steps were optimized for high throughput. Deposition with AlSn or AlSnCu alloys was carried out at coating rates up to 1 μm/s. These alloys, containing elements with different vapor pressures, were evaporated out of one continuously fed crucible with long-term stability. The deposited coatings have finely dispersed tin clusters in the aluminum matrix. The tin clusters have linear dimensions in the range of 200 to 400 nm. This size range is a direct consequence of the high coating rate; it is thus process-specific for EB-PVD. Such coatings are highly beneficial for applications such as plain bearings. Initial load tests have impressively confirmed the advantages for EB-PVD processed bearings. • Aluminum-tin alloys were deposited by EB-PVD at a static deposition rate of up to 1 μm/s. • The pretreatment process and substrate cooling have been optimized for high throughput. • The technology has been adapted to different types of semi-finished products: bearing shells, metal sheets, and strips. • The AlSn coatings have finely dispersed tin clusters with linear dimensions ranging from 200 to 400 nm. • Initial load tests showed a high load capacity of the manufactured bearings. [ABSTRACT FROM AUTHOR]