制动频率对CaSO_4晶须增强树脂基复合摩擦材料性能的影响

Effect of Braking Frequency on Properties of CaSO_4 Whiskers Reinforced Resin-based Composite Friction Materials

采用热模压成型工艺制备CaSO_4晶须增强树脂基复合摩擦材料(试样A),并选用一种市售材料(试样B)作对比,研究制动频率对两种材料摩擦学性能的影响,利用SEM及EDAX观测磨损表面形貌与表面膜成分变化,并分析其磨损影响机理。结果表明:随着制动频率的变化,由于CaSO_4晶须的增韧补强作用,试样A的摩擦因数始终维持在较高水平0.48左右,制动平稳可靠,对偶件损伤程度轻,磨损机理以磨粒磨损为主;而试样B的摩擦因数则是先降低后升高,且对制动速率的变化敏感,磨损机理以黏着磨损和氧化磨损为主。两种材料摩擦表面温度及磨损率均随着制动频率的变化而升高,但在制动频率小于35次时,两种材料均表现出良好的耐磨性。

CaSO4 whisker reinforced resin-based composite friction materials （sample A） were prepared by thermo-compression process, and a commercial brake material （sample B） was selected as a reference. The influence of braking frequency on the tribological performance of samples was investigated by CHASE tester. The SEM and EDAX were used to observe the wear surface morphology and the composition of the surface of films respectively, and the influence mechanism of braking frequency on wear mechanism of samples was analyzed. The results show that CaSO4 whisker has played a significant toughening and strengthening effects on sample A, the average friction coefficient of sample A al- ways maintains at a high level of around 0.48 and exhibits stable and reliable braking performance with the change of braking frequency. Moreover, the damage degree of dual disc is lighter, and the main wear mechanism is abrasive wear. While the friction coefficient of sample B decreases firstly and then increases, and shows sensitive to the change of braking velocity, as well as its main wear mechanism is adhesive wear and oxidation wear. The friction surface temperature and mass wear rate of samples are increased with increasing of braking frequency, but both materials show good wear resist- ance when the braking frequency less than 35 times.