晶须状填料对酚醛树脂摩擦材料性能的影响

Effect of Whiskers-like Fillers on the Phenolic Resin-based Friction Material

研究了分别填充钛酸钾晶须、碳酸钙晶须、针状硅灰石对刹车片摩擦磨损性能的影响。采用MPX-2000和XD-MSM摩擦机对样品进行敏感性和抗热衰退性试验以及定速试验,利用扫描电镜对磨损表面和磨屑进行分析。结果表明,碳酸钙晶须对速度敏感性最低,而钛酸钾晶须对载荷敏感性最低,对速度敏感性最高。钛酸钾晶须的摩擦因数稳定在0.29-0.35,衰退率仅为10%,而碳酸钙晶须和针状硅灰石在250℃后,衰退率高达36%和51%。钛酸钾晶须的磨损率变化平稳,高温段仅是碳酸钙晶须的1/4,针状硅灰石的1/6。钛酸钾晶须有利于形成平整摩擦面,但碳酸钙晶须和针状硅灰石易带来表面磨损。

The effects of potassium titanate whiskers and calcium carbonate whiskers and needle-like wollastonite on the tribological properties of braking friction material were studied. Low temperature tests for speed and load sensitivity measurements and high temperature tests at a constant interval mode to measure fade were evaluated on MPX-2000 tester. Their tribological behaviors were examined on a friction tester with fixed velocity. Morphologies of the worn surfaces and the worn debris were observed by scanning electron microscopy. The results reveal that friction materials filled with calcium carbonate whiskers have the lowest sensitivities to the velocity and potassium titanate whiskers have the lowest sensitivities to the load and the highest sensitivities to the velocity. The friction coefficient of potassium titanate whiskers ranges within 0. 29 - 0. 35 and fade rate is only 10%. Calcium carbonate whiskers and needle-like wollastonite experience serious fade phenomenon above 250 ℃. The fad rates of them are 36% and 51% respectively. The wear rate of potassium titanate whiskers has little fluctuation in the experiment,which is 1/4 of the wear rate of calcium carbonate whiskers and 1/6 of needle-like wollastonite in the high temperature region. Potassium titanate whiskers increase the smooth of friction surface. But calcium carbonate whiskers and needle-like wollastonite lead to the formation of rough rubbing surface.