Ti_(3)SiC_(2)替代石墨对铜基粉末冶金摩擦材料性能的影响

Effect of Ti_(3)SiC_(2) Replacing Graphite on Properties of Copper-based Powder Metallurgy Friction Materials

Ti_(3)SiC_(2)作为一种新型的金属陶瓷材料,具有良好的导热性、耐腐蚀性与高温抗氧化性。探究在动车组粉末冶金闸片中应用Ti_(3)SiC_(2)替代石墨作为润滑相对摩擦材料性能的影响。在粉末冶金闸片摩擦材料中加入不同含量的Ti_(3)SiC_(2)替代石墨,观察摩擦表面氧化膜的变化,分析Ti_(3)SiC_(2)加入量对摩擦材料力学性能和摩擦磨损性能的影响。结果表明:随着Ti_(3)SiC_(2)替代石墨加入量的增加,摩擦材料的剪切强度逐渐提高,使用Ti_(3)SiC_(2)替代全部石墨(质量分数18%)时,剪切强度提高了6倍;在350 km/h高速制动时,摩擦表面形成了氧化膜,随着Ti_(3)SiC_(2)加入量的增加,氧化膜的覆盖面积不断增大并呈现连续分布状态;当Ti_(3)SiC_(2)质量分数大于9%后,在高速制动时摩擦材料的摩擦磨损量和摩擦因数明显降低,Ti_(3)SiC_(2)替代全部石墨后摩擦因数降低了36.8%,摩擦磨损量降低了67.5%。

Ti_(3)SiC_(2) is a new type of cermet material,which has good thermal conductivity,corrosion resistance and high temperature oxidation resistance.The effect of Ti_(3)SiC_(2) replacing graphite as a lubricating phase on the properties of friction materials in the powder metallurgical brake plate of EMU was explored.By adding different content of Ti_(3)SiC_(2) replacing graphite in the friction material of powder metallurgy brake,the change of oxide film on the friction surface was observed,and the effect of the addition of Ti_(3)SiC_(2) on the mechanical properties and tribological properties of brake friction material was analyzed.The results show that with the increase of Ti_(3)SiC_(2) replacing graphite,the shear strength of the friction material gradually increases.When Ti_(3)SiC_(2) is used to replace all graphite(18%in mass fraction),the shear strength increases by 6 times.When the initial braking speed is 350 km/h,oxide film is formed on the friction surface.With the increase of the amount of Ti_(3)SiC_(2),the coverage area of oxide film increases and shows continuous distribution.When the mass fraction of Ti_(3)SiC_(2) replacing graphite is more than 9%,the wear loss and friction coefficient of the friction material decrease significantly,the friction coefficient decreases by 36.8%and the wear loss decrease by 67.5%when replacing all graphite with Ti_(3)SiC_(2).