两种纤维状矿物作为汽车刹车片增强材料的实验研究

Experimental Study on Two Kinds of Fibrous Minerals as Complex Reinforcing Agents of Automotive Braking Block

以改性针状硅灰石和纤维状海泡石作为复合增强体制备了多种刹车片试样,在综合分析各刹车片的冲击强度及定速摩擦试验数据的基础上,优选出了最佳刹车片配方,并针对基于优选配方的刹车片试样进行了卡斯试验及台架摩擦试验测定.结果表明,以1:6(质量分数)的硬脂酸改性细粒(0.018mm,颗粒长径比L∶D>12)针状硅灰石和硬脂酸改性粗粒(0.28mm,L∶D>50)纤维状海泡石作为复合增强体所制备的刹车片的综合性能最佳.基于优选配方所研制的19号刹车片试样的各项性能指标符合汽车刹车片材料国家标准,完全可以替代以石棉摩擦材料为增强材料的刹车片.

A series of automotive braking block specimens were prepared by mold compression at elevated temperature, using cashew oil phenolic resin as the matrix and needle-like wollastonite and fibrous sepiolite modified with stearic acid as the complex reinforcing agents. The impact strengths of the specimens were measured, while their tribological behaviors were examined on a flexed-velocity friction tester, so as to screen the optimized formulation for preparing the brake blocks. Thus the braking block specimen based on the optimized formulation was tested on a CHASE tester and a bench tester, respectively. As a result, the braking block with the proportion of modified needle-like wollastonite to fibrous sepiolite to be 1:6 showed the best comprehensive properties, which could be used to replace the automotive braking block made of asbestos-based friction materials.