混杂纤维增强树脂基摩擦材料研究

发布时间：2018-01-10 15:32

本文关键词：混杂纤维增强树脂基摩擦材料研究　出处：《吉林大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来，车辆行驶速度的不断提高，导致了作为刹车材料使用的摩擦材料的性能需求日益提高。因此，各种先进的材料应用于摩擦材料的研究中，众多新型摩擦材料应运而生。纤维增强树脂基摩擦材料是具有广泛应用前景的一类摩擦材料。通常这类摩擦材料发挥了增强纤维组分的某些优点，使得摩擦材料拥有比传统摩擦材料更优异的性能。两种或多种纤维混杂组成的复合纤维对摩擦材料的增强效果优于单一纤维的增强效果。然而，现阶段，复合纤维的研究只局限在钢纤维和非金属纤维复合方面。因此，本文创新性地将陶瓷纤维和碳纤维混杂，组成碳纤维/硅酸铝陶瓷纤维复合纤维，进而研究其对摩擦材料性能的增强机理。本文以丁腈橡胶改性酚醛树脂、高岭土、氧化铝粉末、硫酸钡为基体，碳纤维、硅酸铝陶瓷纤维为增强体，铝粉、硅粉、镍粉、还原铁粉、铜粉为摩擦性能调节剂，设计合成了树脂基摩擦材料、硅酸铝陶瓷纤维增强树脂基摩擦材料和碳纤维/硅酸铝陶瓷纤维增强树脂基摩擦材料三大类摩擦材料。分别研究了树脂含量、硅酸铝陶瓷纤维含量及混杂纤维含量对摩擦材料的硬度、摩擦系数及其稳定性和磨损率等性能的影响。实验研究表明，丁腈橡胶改性酚醛树脂添加量为18%时，树脂基摩擦材料具有良好的抗热衰退性、稳定的摩擦系数及较小的磨损率。硅酸铝陶瓷纤维的加入提高了陶瓷纤维增强树脂基摩擦材料的低温耐磨性，而随着温度的升高，耐磨性下降，磨损率增大。由于硅酸铝陶瓷纤维脆性大，因此相同温度下，纤维含量越高，摩擦系数和磨损率越大。当陶瓷纤维含量超过9%时，摩擦材料的硬度过大，不符合摩擦材料的实用规范。结果表明，硅酸铝陶瓷纤维含量为6～9%时，硅酸铝陶瓷纤维增强树脂基摩擦材料的增强效果达到最佳状态。碳纤维的耐磨性、高韧性、高导热率等优点，能够对陶瓷纤维的缺点加以弥补，从而能够进一步改善摩擦材料的部分性能。研究发现，当混杂纤维中的碳纤维含量为2～4%，陶瓷纤维含量为4～6%时，摩擦材料的磨损率低，硬度适当，摩擦系数稳定，，且抗热衰退性好。摩擦材料表面磨损形貌观察后发现，不含纤维的树脂基摩擦材料磨损表面光滑，有鱼鳞片状翘起。陶瓷纤维脆性大，导致摩擦材料表面粗糙、表层剥落明显，且裂纹发生几率高。碳纤维的加入，能够促进滑移膜产生，使摩擦表面变得光滑。因此，复合纤维能够有效地降低摩擦表面的粗糙度，阻止剥落和裂纹的发生。
[Abstract]:In recent years, with the increasing of vehicle speed, the performance requirements of friction materials used as brake materials are increasing day by day. Therefore, various advanced materials are used in the research of friction materials. Many new friction materials emerge as the times require. Fiber reinforced resin based friction material is a kind of friction material with wide application prospect. Usually, this kind of friction material has some advantages of reinforcing fiber component. The friction material has better performance than the traditional friction material, and the reinforced effect of two or more fiber hybrid fibers is better than that of the single fiber. However, at present, the research of composite fiber is limited to the composite of steel fiber and non-metallic fiber. Therefore, the ceramic fiber and carbon fiber are mixed creatively in this paper. Carbon fiber / aluminum silicate ceramic fiber composite fiber was formed, and the strengthening mechanism of friction material was studied. In this paper, nitrile rubber modified phenolic resin, kaolin, alumina powder, barium sulfate as matrix, carbon fiber, aluminum silicate ceramic fiber as reinforcement, aluminum powder, silicon powder, nickel powder, reduced iron powder. The resin based friction material was designed and synthesized with copper powder as friction performance regulator. Aluminum silicate ceramic fiber reinforced resin based friction materials and carbon fiber / aluminum silicate ceramic fiber reinforced resin based friction materials three kinds of friction materials were studied respectively. The effects of the content of aluminum silicate ceramic fiber and hybrid fiber on the hardness, friction coefficient, stability and wear rate of friction materials. The experimental results show that the resin based friction material has good heat resistance, stable friction coefficient and low wear rate when the content of NBR modified phenolic resin is 18%. The addition of aluminum silicate ceramic fiber improves the low temperature wear resistance of ceramic fiber reinforced resin based friction material, but with the increase of temperature, the wear resistance decreases and the wear rate increases. Therefore, the higher the fiber content at the same temperature, the greater the friction coefficient and wear rate. When the ceramic fiber content is more than 9, the hardness of the friction material is too large, which does not conform to the code of practice of friction material. When the content of aluminum silicate ceramic fiber is 6 ~ 9, the reinforcement effect of resin based friction material reinforced by aluminum silicate ceramic fiber reaches the optimum state. The advantages of carbon fiber, such as wear resistance, high toughness and high thermal conductivity, can remedy the shortcomings of ceramic fiber and further improve some properties of friction materials. When the content of carbon fiber in hybrid fiber is 2 ~ 4 and the content of ceramic fiber is 4 ~ 6, the wear rate of friction material is low, the hardness is appropriate, the friction coefficient is stable, and the heat resistance is good. After observing the wear morphology of friction material, it was found that the resin based friction material without fiber had a smooth wear surface and a fish scale, and the ceramic fiber had a large brittleness, which resulted in the rough surface of the friction material and the obvious exfoliation of the surface layer. The addition of carbon fiber can promote the formation of slip film and make the friction surface smooth. Therefore, the composite fiber can effectively reduce the roughness of the friction surface and prevent the spalling and cracking.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB34

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