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Applications of nanotechnology in the field of ceramics. The applications of nanomaterials in surface engineering can be categorized into nanofunctional coatings, nanostructured coatings, and nano-composite plating. Nanofunctional coatings refer to coatings that exhibit certain special properties—such as anti-aging, antibacterial, conductive, and stealth properties—due to the incorporation of nanomaterials. Nanstructured coatings refer to coatings whose fineness is reduced to the nanoscale. Dacromet technology and Swandowell GZH technology are two typical nanostructured coatings. The former coating has properties similar to those of a zinc coating; it can provide sacrificial anode protection for steel substrates. Its structure is similar to that of zinc-rich paint, with chromium compounds serving as a binder between flaky zinc powder and aluminum powder (in the micron range). The application process of this coating is similar to that of thermosetting coatings. This technology has advantages such as low pollution, high corrosion resistance, and no hydrogen embrittlement. The latter technology belongs to aqueous phosphate coating technology, which itself serves three functions: shielding, anode protection, and corrosion inhibition. The zinc powder and aluminum powder used in this technology are ordinary powders with large particle sizes; as a result, thick coatings (50–60 mm thick) are required to achieve their three main functions. If nanoscale flake zinc and aluminum powders are used to replace conventional zinc and aluminum powders in these two technologies, it is possible to maintain their original properties while significantly reducing the thickness of the coating, thereby improving the dimensional accuracy of the coating. Moreover, due to the finer texture of the flake zinc powders, the sealing property of the coating improves, which greatly enhances its corrosion resistance and thus expands the scope of application for this technology. The powders used in current composite plating technologies are all ordinary powders; while certain functions can be achieved, the large particle size of these powders results in reduced shielding properties of the coating, thereby lowering its corrosion resistance. The use of nanometal powders allows the powder to be completely enclosed within the coating, eliminating the side effects associated with ordinary powders, and resulting in a smooth and fine surface on the coating ； Heat treatment of the nano-composite coating is carried out to cause the metal nanoparticles to fuse with the metal of the coating, resulting in a corresponding alloy coating. This approach can replace the current alloy electroplating techniques and simplify the maintenance of the plating solution.