高温高圧アンモニア水溶液環境下におけるa-C:H膜の摩擦摩耗特性

抄録

In recent years, technological developments have been progressing to utilize ammonia as a carbon-free fuel. Ammonia has the advantage of being able to use existing infrastructure technologies for storage and transportation, but it is a corrosive substance. Therefore, materials used in the operational environment of ammonia fuel require corrosion and wear resistance. The application of DLC (diamond-like-carbon) coating, which exhibit excellent chemical stability and wear resistance, is highly anticipated in this context. In this study, friction tests were conducted on a-C:H coating in high-temperature, high-pressure ammonia water using an autoclave-type high-temperature, high-pressure friction test machine that can simulate the operational environment of the fuel. The results showed that the wear amount of the a-C:H coating increased with the concentration of ammonia water. To clarify the cause, AES analysis and AFM nano-scratch tests were conducted. The results suggested that the increased wear was likely due to softening caused by oxidation of the film's outermost surface.