The core requirements for trains (including high-speed EMUs, intercity trains, subways, and maglev trains) are weight reduction (to lower energy consumption and track wear), enhanced structural strength (to ensure operational safety), and optimized passenger experience (to minimize vibration and noise). Carbon fiber, with its properties of high specific strength, low density, fatigue resistance, and excellent vibration damping, has gradually replaced traditional metallic materials such as steel and aluminum alloys.