There are three main ways of heat transfer on urban rail transit vehicles: heat conduction, convection, and radiation. In order to reduce the discomfort caused by vehicle heat transfer to passengers, reduce vehicle energy loss, and improve energy utilization, insulation materials must be laid in appropriate positions inside the vehicle body. Considering the insulation and fire protection requirements of vehicles, insulation materials must have the characteristics of flame retardancy, non toxicity, good insulation and sound absorption performance.