改性酚醛树脂对摩擦片制动性能的影响

Influence of modified phenolic resin on braking performance of friction disc

采用热压烧结技术制备了以酚醛树脂、腰果壳油改性酚醛树脂以及环氧改性酚醛树脂为基体的3种树脂基摩擦片试样(依次为试样A、试样B和试样C)。利用环-块摩擦磨损试验机研究这3种试样在不同制动速度、不同压力下的性能,并采用JSM-IT300扫描电镜对它们的磨损表面形貌进行分析。结果表明:试样B表面显微结构较为密实,没有空洞和裂纹,不同组分均匀分布于基体中,并且在不同制动条件下具有较为稳定的摩擦因数和较小的磨损率,对偶制动轮磨损也较小;3种试样摩擦表面均有摩擦膜的形成,试样A的摩擦膜形成较差,磨损机理表现为粘着磨损和磨粒磨损,且以磨粒磨损为主;试样B的摩擦膜较为平整均匀,磨损机理主要为微犁沟和疲劳剥落;试样C的摩擦膜形成依托于硬质相,磨损机理为磨粒磨损。

Three kinds of friction disc samples matrixed by pure phenolic resin, cashew nut shell oil（CNSL） modified phenolic resin, and epoxy modified phenolic resin（termed as sample A, sample B and sample C in sequence） were prepared by hot-press sintering method. Their tribological properties were investigated by applying ring-block friction wear tester at various braking speed and load, and their worn surface were analyzed by applying JSM-IT300 SEM. The results indicated： the surface microstructure of sample B appeared considerably compact without pores and cracks, various components uniformly distributed in the matrix, and at various braking conditions, it showed considerably stable friction coefficient and low wear rate, as well as its matched braking wheel wore a little; there was friction film formed on the surface of three samples, sample A possessed poor friction film characterized by adhesive wear and abrasive wear, in which the abrasive wear was dominant; sample B possessed considerably flat and even friction film characterized by micro-plough and fatigue spalling; sample C possessed hard friction film characterized by abrasive wear.