Objective The high-speed EMU (electric multiple unit) bogie is a core load-bearing component of the train, and its performance is directly related to the operational safety. Under severe working conditions such as wind and snow, the bogie area is easily subjected to complex airflow fields, and ice accumulation is particularly prominent, which can significantly alter the fit tolerances of key moving components, interfere with the dynamic response characteristics of the braking system, and cause functional abnormalities in the on-board signaling system. Therefore, it is necessary to develop a composite coating system with hydrophobic and anti-icing functions using acrylic resin as the matrix.

Method Acrylic resin exhibits excellent film-forming properties and weather resistance, and has good compatibility with functional additives, providing a stable base structure for the coating. Using acrylic resin as the main film-forming substance, the addition-type room-temperature-curing liquid silicone rubber is selected as the core additive component. Its curing process produces no small-molecule by-products, exhibits no shrinkage, and demonstrates outstanding flexibility and low surface energy characteristics, which can effectively regulate the mechanical properties and interfacial characteristics of the coating. Perfluoroalkyl phosphate and nano-SiO₂ are introduced to form a stable coating system, and the anti-freezing adhesion performance of the coating is systematically studied, including the normal and shear freezing adhesion strength of ice and the freezing adhesion force.

Result & Conclusion  As the silicone content increases, the normal and shear freezing adhesion strength first decreases and then increases. The friction loss and overall hardness of the anti-freezing adhesion coating are inversely proportional to the increase in silicone content. When the silicone content is 13 wt%, the freezing adhesion strength of the coating reaches the highest.