动车组制动闸片基体材料的设计开发

Design and development of the matrix materials for brake pads on EMUs

采用机械合金化方法制备特种工况动车组制动闸片的基体材料。以Cu50Fe50混合粉末为研究对象,研究了球磨时间、球磨转速、球料比、球磨介质等因素对材料压制性能的影响。结果表明:随球磨时间的延长,球料比增加,合金化粉末的粒度越小,材料的压制性能逐渐提高;选择无水乙醇作为球磨PCA的粉末表面无“疏水膜”具有更好的压制性能。针对Cu50Fe50粉末,以无水乙醇作为PCA、球料比20∶1、转速300 r/min、球磨48 h的混合粉末具有更好的压制特性,压制得到的粉末压坯密度高达7.12 g/cm^(3)。

The matrix materials of brake pads of EMUs under harsh operating conditions are prepared by means of mechanical alloying method.With Cu50Fe50 mixed powder being the research object,the influence of ball-milling time,ball-milling speed,the ratio of grinding ball to material and milling medium on the pressing properties of Cu50Fe50 powder is studied.The results show that with the increase of milling time,grinding ball to material ratio,the particle size of the alloyed powder decreases;and the pressing property of the material increases gradually.Choosing anhydrous ethanol as the powder for ball milling PCA without a hydrophobic film on the surface generates a better compaction performance.For Cu50Fe50 powder,with the anhydrous ethanol functioning as PCA,a grinding ball to material ratio of 20:1,a rotating speed of 300 r/min and a ball-milling time of 48h could achieve better compaction characteristics.The density of powder compact obtained by pressing is as high as 7.12 g/cm^(3).