碳布增强湿式摩擦材料摩擦学性能及机理研究

发布时间：2018-01-04 23:02

  本文关键词：碳布增强湿式摩擦材料摩擦学性能及机理研究　出处：《陕西科技大学》2015年硕士论文　论文类型：学位论文

  更多相关文章： 湿式摩擦材料 碳布增强 摩擦学性能 水热氧化 纳米SiO2

【摘要】：树脂基复合材料作为湿式摩擦材料的重要组成广泛应用于汽车自动变速器、同步器、差速器以及扭矩管理器等方面,随着技术的不断进步,高铁、地铁、大型工程机械、深海石油钻井等的传动/制动系统对树脂基复合材料的工况适应性、传动平稳性以及使用寿命等方面提出了更为苛刻的要求。本文以碳布为增强体,研究了不同改性酚醛和不同对偶材料对碳布增强湿式摩擦材料摩擦学性能的影响,重点研究了水热氧化法改性碳布和微波水热法沉积纳米Si O2改性碳布对摩擦材料的影响。(1)采用硼改性、腰果壳油改性和丁腈橡胶改性酚醛树脂制备了三种碳布增强湿式摩擦材料,并采用热分析仪分析了样品的热降解特性,湿式摩擦试验机测试了样品的摩擦磨损性能,扫描电子显微镜分析了样品的磨损机制。结果表明:由硼改性酚醛树脂制备的碳布增强湿式摩擦材料表现出良好的耐热性,更高的摩擦系数,优异的摩擦稳定性和较低的磨损率。(2)采用水热氧化法在不同水热温度下用浓硝酸处理碳布,详细研究了水热温度对摩擦学性能的影响规律。结果表明:经不同水热氧化温度改性后的碳布表面形貌发生变化,同时出现了大量的羰基基团,碳纤维石墨化程度有所提高,碳布表面亲水性能得到了明显的改善,有效提高了碳布与树脂的粘结强度。水热氧化改性碳布增强湿式摩擦材料在100-120℃表现出最佳的摩擦磨损性能,磨损量分别降低到了未改性样品的34.3%和44.7%。(3)在水热100℃条件下氧化处理碳布的基础上,采用微波水热法,在不同微波水热温度、硅溶胶浓度和微波水热时间下引入纳米Si O2颗粒,系统研究纳米Si O2对碳布增强湿式摩擦材料的影响。结果表明:纳米Si O2颗粒有效沉积到了碳纤维表面,增加了碳纤维表面的粗糙度和碳布亲水性能,实现了复合材料的多尺度增强。微波水热200℃、硅溶胶浓度9%和微波水热60min条件下沉积纳米Si O2改性碳布增强湿式摩擦材料的摩擦学性能最好,动摩擦系数和摩擦稳定性均有所提高,同时磨损量降低到了未改性样品的20.8%。(4)在水热100℃条件下氧化处理碳布的基础上制备碳布增强湿式摩擦材料,分别与以45#钢、Cr12钢、不锈钢、铜为对偶材料进行了摩擦磨损性能的测试,研究了不同对偶材料对碳布增强湿式摩擦材料摩擦学性能的影响。结果表明:以铜为对偶材料时,在磨损过程中铜逐渐从对偶面转移到摩擦材料表面,主要以黏着磨损为主,大大降低了对摩擦材料的损伤;以45#钢为对偶材料时,摩擦材料以磨粒磨损和黏着磨损为主,耐磨性能有所下降;以不锈钢、Cr12为对偶材料时,碳布增强湿式摩擦材料出现大量的纤维断裂现象,磨损机理主要以磨粒磨损为主,导致了较高的磨损。
[Abstract]:As an important component of wet friction materials, resin matrix composites are widely used in automotive automatic transmission, synchronizer, differential and torque management. With the development of technology, high-speed rail, subway. The adaptability of transmission / braking system of large-scale construction machinery, deep-sea oil drilling and so on to resin matrix composites. More stringent requirements are put forward in terms of transmission smoothness and service life. Carbon cloth is used as reinforcement in this paper. The effects of different modified phenolic and dual materials on tribological properties of carbon cloth reinforced wet friction materials were studied. The effects of hydrothermal oxidation and microwave hydrothermal deposition of nano-SiO _ 2 modified carbon cloth on friction materials were studied. Three kinds of carbon cloth reinforced wet friction materials were prepared by cashew shell oil modification and acrylonitrile rubber modified phenolic resin. The thermal degradation characteristics of the samples were analyzed by thermal analyzer. The friction and wear properties of the samples were tested by wet friction tester. The wear mechanism of the samples was analyzed by SEM. The results showed that the carbon cloth reinforced wet friction materials prepared by boron modified phenolic resin showed good heat resistance and higher friction coefficient. Excellent friction stability and low wear rate. 2) carbon cloth was treated with concentrated nitric acid at different hydrothermal temperatures by hydrothermal oxidation. The effect of hydrothermal temperature on tribological properties was studied in detail. The results showed that the surface morphology of carbon cloth modified by hydrothermal oxidation temperature changed and a large number of carbonyl groups appeared at the same time. The graphitization degree of carbon fiber was improved, and the surface hydrophilicity of carbon cloth was improved obviously. The bonding strength between carbon cloth and resin was improved effectively. The hydrothermal oxidation modified carbon cloth reinforced wet friction material showed the best friction and wear performance at 100-120 鈩，

本文编号：1380460