Al_2O_3和SiO_2质量分数配比对铜基粉末冶金制动材料摩擦磨损性能的影响

Effect of Mass Fraction Ratio of Al_2O_3 to SiO_2 on Friction and Wear Properties of Cu-based Powder Metallurgy Brake Material

为了提高制动闸片的使用性能,采用粉末冶金技术制备Al_2O_3和SiO_2质量分数配比分别为2∶6、4∶4、6∶2和8∶0的铜基摩擦材料,测定其密度和硬度。用MM1000-Ⅱ型摩擦磨损试验机测试其摩擦磨损性能;用扫描电镜观察其表面的摩擦形貌,并分析其摩擦磨损机制。分析结果表明:随着Al_2O_3质量分数的增加,制动材料的孔隙率减小,布氏硬度增加。当制动初速度较低(2303 r/min)时,随着Al_2O_3质量分数的增加,制动材料的摩擦因数减小,耐磨性能逐渐提高;当制动初速度较高(5 757 r/min)时,随着Al_2O_3质量分数的增加,制动材料的摩擦因数减小,耐磨性能先升高后降低。

In order to improve the performance of brake pad,the powder metallurgy technology was used to produce Cu-based friction material,in which mass fraction ratio of Al_2O_3 to SiO_2 was 2∶ 6,4∶ 4,6∶ 2 and 8∶ 0,respectively. The density and hardness of the material were measured. The friction and wear properties of the material were measured by MM1000-Ⅱ type friction and wear tester. The wear surface morphology of the material was observed by scan electron microscope. The friction and wear mechanism of the material were analyzed. The results show that the porosity of brake material decreases and the Brinell hardness increases with the increase of Al_2O_3 mass fraction. When the initial braking speed is at lower speed( 2 303 r/min),the friction factor of brake materials reduces with the increase of Al_2O_3 mass fraction,and the wear resistance increases gradually. When the initial braking speed is at higher speed( 5 757 r/min),the friction factor of brake materials decreases with the increase of Al_2O_3 mass fraction,and the wear resistance increases firstly and then decreases.