汽车刹车片用铁铜基摩擦材料的研究

Study of Fe and Cu-based P/M friction materials for automotive brake pads

采用粉末冶金热压技术制备铁铜基刹车片材料,进行磨损试验和扫描电镜观察。结果表明:将粒度53～74μm的电解Cu粉、Fe粉、石墨、Ti、Ni、SiO2、Al2O3、MoS2混合均匀,于450～550MPa的压制压力下模压成形,在1 000℃、2.5～2.8MPa压力下N2保护热压1～2h,可制备出汽车刹车片用铁铜基摩擦材料。其显微组织由粘结的基体Fe、Cu相,耐磨的陶瓷、碳化物相和一些润滑相所构成;所制备材料的密度为5.57 g/cm3,平均硬度是227HV。影响其摩擦性能的主要因素是法向压力和转速,与钢的磨损速率为0.002 6 g/min,摩擦系数0.45;磨损的失效机理是先期粘着磨损,随后转化为磨料磨损,但以磨料磨损为主。

A kind of iron-copper based fricition material for automotive brake pad was prepared by powder metallurgy technology： mixing of electrolytic copper powder with particle size of 53-74μm and iron,graphite,titanium,nickel,silica,aluminum oxide and vulcanized molybdenum powder,compaction forming at 450-550MPa,hot pressing sintering at 1 000℃ and pressure of 2.5-2.8MPa for 1-2h.The microstructure consist of iron and copper,ceramic,carbide and additives,the density and hardness of the friction materials is 5.57 g/cm3 and 227HV,respectively.By the wear testing,the wear rate and friction factor of the friction materials is 0.002 6 g/min and 0.45,respectively.The influence factor of the friction materials is normal presser and rotate speed,the failure mechansm is adhere wear at first and grinding compound wear mostly.