硅氧烷改性环氧树脂对铝基复合材料制动盘配套闸片摩擦系数的影响

Effect of Siloxane Modified Epoxy Resin on Friction Coefficient of Brake Disc with Aluminum Matrix Composite

以端羟基聚二甲基硅氧烷(HTPDMS)与环氧树脂(EP)为原料,合成了硅氧烷改性环氧树脂(ES),用其与热固性酚醛(PF)共混(PF/ES)作为黏结剂,与PF、PF与EP共混物(PF/EP)进行比较,研究其耐温性和韧性。并制备了匹配铝基复合材料(AMMC)制动盘的闸片材料,探讨了多种压力和转速条件下黏结剂对刹车片摩擦性能的影响。结果表明,引入HTPDMS提高了EP的耐温性,与PF共混后700℃以上残留物质量较PF提高181.1%;PF/ES具有较高的韧性,其冲击强度较PF和PF/EP分别提高467.1%、270.4%;采用PF/ES制备的闸片在停车制动和高温制动中摩擦系数(COF)稳定、大小适宜、不伤盘;共聚焦显微镜下观察在停车制动阶段出现了不连续的转移膜,主要的磨损形式为黏着磨损、疲劳磨损,高温制动时PF/ES制备的闸片表面存在碳化膜,主要磨损形式为磨粒磨损和氧化磨损。

Using hydroxy-terminated polydimethylsiloxane(HTPDMS)and epoxy resin(EP)as raw materials,the siloxane modified epoxy resin(ES)was synthesized,and the thermosetting phenolic resin(PF/ES)was used as the binder.The temperature resistance and toughness of ES were studied by comparing with PF and PF/EP blends.The brake pad material matching Aluminum matrix composite(AMMC)brake disc was prepared,and the influence of adhesive on the friction performance of brake pad under various pressure and speed conditions was discussed.The results show that the temperature resistance of EP is improved by the introduction of HTPDMS,and the residue quality of EP at 700℃is increased by 181.1%comparing with PF.The impact strength of PF/ES is 467.1%and 270.4%higher than that of PF/EP.The brake plate prepared by PF/ES has stable friction coefficient(COF),suitable size and no disc damage in parking braking and high temperature braking.Under confocal microscope,discontinuous transfer film appeared in the parking brake stage,and the main wear forms are adhesive wear and fatigue wear.There are carbonized film on the surface of brake plate prepared by PF/ES during high temperature braking,and the main wear forms are abrasive wear and oxidation wear.