The friction coefficient of high-speed braking is improved by using new ferroalloy (ferrophosphorus, ferromolybdenum) to improve the friction coefficient of high-speed braking and smooth braking process; non-metallic friction parts and lubricating parts with high volume ratio (≥ 40%) are used to improve the high-temperature resistance and braking performance of the new copper based powder metallurgy friction material to meet the high-speed braking requirements of 300km / h high-speed train; aviation kerosene and latex new molding agents are used to reduce the friction coefficient of high-speed braking The forming pressure of low volume ratio non-metallic friction material solves the technical problem of forming difficulty caused by cracking. A new type of copper based powder metallurgy brake pad friction material for high-speed train and its preparation process were obtained by adopting the sintering technology of segmented adding muffler middle section heating and pressing to solve the technical problem of sintering deformation of brake pad material with large diameter ratio. This product is a heating valve body of middle muffler, which belongs to box parts. There's a couple of guys in it. Shrinkage holes were found on the surface of the boss during machining. After repeated rectification (from the aspects of process, batching, smelting, etc. ）There is no improvement. About 10% of the products are found to have this problem every time they are delivered.