摩擦材料用改性酚醛树脂的研究进展

酚醛树脂是摩擦材料中最重要的基体材料，但是纯酚醛树脂存在脆性大、耐热性不足等缺陷，因此要对酚醛树脂进行改性以提高其耐热性和韧性。主要介绍了近年来常用的几种化学改性酚醛树脂和物理改性酚醛树脂及其对摩擦材料性能的影响。     

树脂基刹车片的改性研究进展

综述了树脂基刹车片的改性研究进展，主要介绍了树脂基体改性、增强纤维与摩擦调节剂的改变对刹车片的性能的影响。     

纳米钛/锌改性酚醛树脂涂料及耐蚀性能研究

因纳米钛和纳米锌具有较好的耐腐蚀特性，为提高酚醛树脂涂料的应用领域。本文研究了纳米钛/锌改性的酚醛树脂涂料及其耐蚀性能。利用扫描电子显微镜(SEM)、傅里叶变换红外光谱(FTIR)、紫外-可见光谱(UV-VIS)、盐雾实验箱等方法对涂层的微观结构和耐蚀性能进行了表征。结果表明，傅里叶红外光谱图曲线在655cm^-1处出现了Ti-O弯曲振动峰、在599cm^-1处出现了ZnO特征吸收峰成功制备了纳米钛/锌改性酚醛树脂涂料；紫外-可见光谱曲线在170～185 nm的紫外光区出现了不同程度的吸收，即得到了纳米钛/锌改性酚醛树脂涂料且涂料耐紫外性得到了明显的提高。利用物理分散技术与化学分散技术相结合的方法，纳米钛/锌粒子在酚醛树脂中分散均匀，部分区域发生微团聚；纳米钛/锌改性酚醛树脂涂料在3.5%NaCl水溶液在720 h出现锈蚀，其耐蚀性能远优于未改性酚醛树脂涂料。     

纳米SiC改性酚醛树脂的热稳定性

用超声波对纳米SiC进行物理分散,用偶联剂对其进行表面化学改性,以获得纳米粒子分散良好、界面结合良好的纳米SiC改性酚醛树脂;根据改性酚醛树脂的DTA-TG试验结果分析其热稳定性。结果表明:纳米SiC改性酚醛树脂较纯酚醛树脂的热稳定性要好,其中SiC纳米粒子含量为树脂的5%的改性酚醛树脂S05的热稳定性提高最大;经表面改性的SiC纳米粒子改性酚醛树脂S05较未进行表面改性的SiC纳米粒子改性酚醛树脂S05G的热稳定性提高要大。     

桐油改性线型酚醛树脂的制造及应用研究

介绍桐油改性线型酚醛树脂的制造方法及应用研究。苯酚，甲醛，桐油在酸催化下进行加成缩合聚合反应制得的桐油改性线型酚醛树脂，是国内我未见报导的桐油改性酚醛树脂新品种。用该树肥作为粘接制造的汽车摩擦材料的主要性能指标，均超过国家规定的标准。其中，刹车片衬片的缺口冲击强度平均达到了４．１１ｄＪ／ｃｍ＾２，离合器面片的弯曲强度平均达到了５４．４ＭＰａ，最大应变平均达到了９．２×１０＾－３ｍｍ／ｍｍ。对制品的     

高性能改性酚醛树脂的研究进展

酚醛树脂是树脂结合剂金刚石砂轮中重要的结合剂材料,但是普通的酚醛树脂由于存在脆性大、韧性和耐热性能不足的特点,限制了它在树脂结合剂金刚石砂轮中的应用。因此,需要对普通的酚醛树脂进行改性以提高其耐热性及韧性。综述了从化学和物理两方面提高耐热性的改性方法以及从内增韧和外增韧两方面提高韧性的改性方法,以期改性后的酚醛树脂在树脂结合剂金刚石砂轮中得到更广泛的应用。     

阻燃酚醛型舱内材料抗冲击性的改进研究EI

本文通过采用活性增韧和物理共混增韧的方法对酚醛树脂进行了改性，使复合材料的抗冲击性有了很大提高。所研制的复合材料各项性能符合指标要求。     

胶乳改性摩阻材料用酚醛树脂的研究

采用丁腈，羧基丁腈，丁苯，丁吡四种胶乳改性酚醛树脂，研究改性产生的微观结构与其冲击强度和摩擦性能之间的内在关系，实验结果表明，胶乳改性酚醛树脂在性能上有强度大且韧性好的特点，尤其在摩擦性能上比纯酚醛树脂有较大的改善，通过四种胶乳改性酚醛树发现，羧基丁腈胶乳改性酚醛树脂综合性能优于其它三种胶乳改性的酚醛树脂。     

梓油改性酚醛树脂的合成及结构分析

用我国湖北省产的梓油，合成了改性酚醛树脂，并对反应机理和树脂结构进行了分析。结果表明，当梓油含量不苯酚含量为３０－６０％时，改性酚醛树脂的性能最好。在改性酚醛树脂交联固化过程中所形成的ＩＰＮ结构，提高了酚醛树脂的韧性的耐热性。     

改性酚醛树脂处理剂对石英纤维增强芳基乙炔复合材料性能的影响

采用改性酚醛树脂作为石英纤维表面处理剂来提高石英纤维增强芳基乙炔复合材料(SF/PAA)界面性能。通过性能测试,研究处理剂对力学性能和介电性能的影响。通过XPS和SEM分析方法,研究了酚醛树脂表面处理剂对复合材料界面官能团变化和微观形貌的影响。性能测试结果表明改性酚醛树脂处理剂可以显著提高PAA复合材料的力学性能和介电性能。XPS分析结果表明酚醛树脂处理后的石英纤维表面与酚醛树脂发生了化学反应,SEM研究表明酚醛树脂处理后的复合材料界面粘结性能得到显著提高。     

汽车树脂基刹车材料的摩擦机理及其对刹车材料的要求

介绍了汽车刹车材料的摩擦磨损理论,在此基础上对树脂基刹车材料及其原材料的要求做了综述性介绍.指出:①对酚醛树脂进行增韧和耐热改性是刹车材料用酚醛树脂的重要研究方向;②混杂纤维是增强纤维研究的重要内容;③填料的作用不可忽视.最后提出高性价比的环保型刹车材料是刹车材料的研究方向.     

提速列车制动闸片的研制

以短切炭纤维、金属纤维等混杂纤维为增强材料制备了适用于我国提速列车客车车辆用的酚醛树脂基盘型制动闸片材料。用扫描电镜检测混料效果，用聚速板制订合理的热压成型工艺参数，用列车台架试验不同制动初速度时紧急制动，常规制动和洒水制动条件下闸片的制动特性。结果表明，研制的提速列车制动闸片材料的机械性能和制动特性指标都达到了我国铁道部门的相应技术要求，其摩擦性能在整个制动过程均十分平稳。     

摩擦材料用有机粘接剂的研究与进展

有机粘接剂是摩擦材料中最关键的基体组分,它将各种成分紧密地粘合在一起以获得所需性能,其性能好坏直接影响摩擦材料性能的发挥,尤其是其耐温性决定着摩擦材料的使用性能。文中综述了近年来摩擦材料用有机粘接剂的研究与进展,重点介绍了酚醛树脂(PF)粘接剂的改性研究概况,希望为高性能摩擦材料用粘接剂的研制提供一些资料积累和思路。     

现代轨道交通刹车材料的发展与应用

分析了轨道交通车辆用盘形制动装置中闸片/制动盘组成的摩擦副的工作条件及其对材料的要求,介绍了铸铁闸片、树脂基闸片、铁基和铜基粉末冶金闸片的性能特点及适用领域,重点分析了粉末冶金闸片各组元的功能及摩擦磨损性能调控机制.基于制动盘热斑形成机理,阐明了闸片形状与排布对制动盘热源分布的影响规律.阐述了铸铁、铸钢、锻钢、金属基复合材料和C/C复合材料制动盘的研究进展,并指出了现代轨道交通刹车材料设计与制造的研究热点及研究方向.     

Effects of Mixing the Steel and Carbon Fibers on the Friction and Wear Properties of a PMC Friction Material

Friction, fade and wear characteristics of a PMC friction material containing phenolic resin, short carbon fiber, graphite, quartz, barite and steel fiber were investigated through using a small-scale friction testing machine. Four different friction materials with different relative amounts of the carbon fiber and steel fiber were manufactured and tested. Comparing with our previous work which contained only steel fiber as reinforcement, friction characteristics such as fade and recovery and wear resistance were improved significantly by adding a small amount of carbon fiber. For the mixing of carbon and steel fiber, the best frictional and wear behavior was observed with sample containing 4 weight percentage carbon fiber. Worn surface of this specimen was observed by optical microscopy. Results showed that carbon fibers played a significant role in the formation of friction film, which was closely related to the friction performance. The brake pad with Steel fibers in our previous work, showed low friction coefficient and high wear rate. In addition, a friction film was formed on the surface with a relatively poor quality. In contrast, the samples with mixing the steel and carbon fiber generated a stable friction film on the pad surface, which provided excellent friction stability with less wear.     

Frictional performance evaluation of newly designed brake pad materials

This work is aimed to study the tribological properties difference of potentially new designed non-commercial brake pad materials with and without asbestos under various speed and nominal contact pressure. The two fabricated non-commercial asbestos brake pad (ABP) and non-asbestos brake pad (NABP) materials were tested and compared with a selected commercial brake pad (CMBP) material using a pin-on-disc tribo-test-rig under dry contact condition. Results showed that friction coefficients for all materials were insensitive to increasing speed and pressure. NABP maintained stable frictional performance as ABP material when contact temperature elevated. Moreover, NABP proved to have greater wear resistance compared to ABP and CMBP materials. Furthermore, the SEM micrographs of brake pad surfaces showed craters which is due to disintegration of plateaus. Finally, the test results indicated that the NABP has the potential braking characteristic for a brake pad material.     

Performance evaluation of brake pads developed using two different manufacturing methods

The aim is to study the effect of several distinct manufacturing processes, parameters and ingredients on the physical, mechanical and frictional characteristics of brake pad developed using hand lay method (sample 1), brake pad developed using hot compression method (sample 2) and commercial brake pad (sample 3). The non asbestos brake pad samples were compared with the selected commercial brake pad sample using pin on disc test set up. Results showed that friction performances of all three samples were insensitive to water and oil absorption test. Sample 2 had better mechanical properties and greater wear resistance than other two samples which are attributed to use of hot press method of manufacturing the composite and selecting the carbon-based ingredients. Sample 1 maintained high coefficient of friction even though manufactured with the help of hand lay method. Both fabricated brake pads are stable upto the temperature 220 °C without any weight loss and degradation. Brake pad surfaces showed different shape wear debris and plateaus significantly affecting the friction characteristics. Finally, the test results indicated that both fabricated brake pad samples have potential braking characteristics to be used as a brake pad material.     

三聚氰胺和腰果壳油改性酚醛树脂的研究

用腰果壳油和三聚氰胺对酚醛树脂进行改性,可用作刹车片中各种基料的胶粘剂。研究了反应物配比、催化剂用量和反应时间等因素对改性树脂性能的影响,确定了最佳配比和生产工艺,并成功的应用于工业生产。     

改性酚醛树脂陶瓷摩擦材料的摩擦磨损性能

以普通酚醛树脂、硼改性酚醛树脂、三聚氰胺改性酚醛树脂为黏结剂,以陶瓷纤维为增强纤维,制备了3种酚醛树脂陶瓷摩擦材料。对其冲击韧性和硬度进行实验测试,采用摩擦磨损试验机考察其摩擦磨损性能,采用扫描电子显微镜(SEM)和X射线能谱仪分析其磨损表面形貌及其成分,并探讨其磨损机制。结果表明:硼改性酚醛树脂黏结剂能够提高摩擦材料的硬度,三聚氰胺改性酚醛树脂黏结剂能够提高摩擦材料的冲击韧性,降低摩擦材料硬度;在摩擦过程中三聚氰胺改性酚醛树脂在高温下炭化,在摩擦材料表面形成一层致密的摩擦层,摩擦层的存在使摩擦材料的摩擦因数相对比较稳定,降低了摩擦材料的磨损率。