Multifunctional Coating System for Rail Track Applications

This study focused on development and characterization of a multifunctional coating system for rail track applications, such as low solar absorption, long-term durability, and corrosion resistance. Both laboratory and field experiments were conducted using coated and uncoated rails exposed to sunlight at various ambient temperatures to evaluate the effectiveness of coating in reducing rail temperature. The experimental results show that the average temperature reduction provided by the coating was 10–25°F, depending on the peak air temperature and measurement method. The effect of measurement method on rail temperature was investigated using different instrumentation types (magnet sensor, thermocouple, and automated Salient system) and thermal modelling simulations. On the other hand, the coated rail segments were placed in to the accelerate corrosion testing in a customized chamber to evaluate the performance of coating under exposure of wet/dry and freeze/thaw cycles, UV radiation, and salt spray. The performance of the coated rail segments placed in the outdoor environment and the coated rail track at service were used to evaluate the durability of coating. Field application of coating demonstrates that the coating adheres well to the rails. The curing time is about an hour. The coating can be applied on active tracks with proper scheduling. The durability of the coating was observed over two winter seasons.