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第43卷，第11期 2015年11月
doi:10.3969/j.issn.1001-3539.2015.11.010
工程塑料应用 ENGINEERING PLASTICS APPLICATION
Vol.43, No.11 Nov, 2015
汽车止推垫片注塑成型工艺及性能研究
杨培娟"，黄健？
(1.浙江经贸职业技术学院，杭州310018；2.杭州塑盟特科技有限公司，杭州311254)
摘要：以聚酰亚胺(PI)为主体材料，添加少量的石墨和聚四氟乙烯，通过挤出成型工艺得到PI复合颗粒。并进一步注塑成型为汽车用止推垫片，主要探讨了注塑成型温度和压力对其成型性能和力学性能的形响。结果表明，随着注整温度升高，PI试样的拉伸强度、冲击强度和压缩强度都提高，当注望温度超过360℃时，力学性能有所下降，注塑温度过高或过低都会使试样性能下降；在合适的注望温度下，适当提高注塑压力，有利于提高试样的力学性能。最佳的注塑工艺条件为：注塑温度为360℃，注压力为120～150MPa。对在最佳工艺条件下注的PI试样，用退火的方式进行热处理，发现在200℃时处理30min，试样的力学性能最佳。通过优化注塑成型工艺制备的汽车用止推垫片性能优异、耐温性好、抗烯变强、耐座性佳、耐油性好、力学强度高，而且阻燃性能优异，完全符合汽车用止推垫片性能要求。
关键调：热塑性聚酰亚胺；注塑成型；止推垫片
中图分类号：TQ323.7
文献标识码：A
文章编号：1001-3539(2015)11-0044-04
StudyonInjectionMoldingTechnologyand Propertiesof ThrustWasher
YangPeijuan',Huang Jian?
(1. Zhejiang Economic &Trade Polytechnic, Hangzhou310018, China ;2. Hangzhou Surmount Sci.&Tech Co., Ld., Hangzhou 311254, China)
Abstract : By using thermoplastic polyimide (PI) as the matrix and some graphite and PTFE, the composite pellets were made through extrusion process., Taking these pellets as raw material for injection molding into thrust washer, the effects of injection temperature and pressure on the molding properties were also investigated. The results show that with the increase of the injection ooaasesasssaeaeaaaa temperature is above 360°C , the mechanical properties of the samples molded decrease. As the injection temperature is fixed at 360°C, increasing the injection pressure can improve the molding properties. The optimal injection molding conditions of TPI are that aeaeesseea conditions were treated by annealing method. It is found the optimal annealing process is putting the samples molded at 200°C for 30 min. At last, the thrust washer samples of the automobile vehicle were produced at the optimal injection molding condition. The properties of the products were also investigated. The Thrust washers have high temperature performance, low thermal expansion coefficient, low friction coefficient, excellent oil resistance, good mechanical properties, and excellent flame retardant. In a word the thrust washers molded meet the requirements for the automobile vehicle
Keywords ; thermoplastic polyimide;injection molding ; thrust washer
止推垫片是汽车中必不可少的零部件之一，其主要功能是当汽车在行驶中发动机曲轴受到热膨胀而伸长或受斜齿轮及离合器等轴向力作用而产生轴向移动时，避免曲轴与机体间产生直接接触。止推垫片最早采用进口铜铅合金双金属带加工而成。因为金属止推垫片摩擦性能不稳定，容易发生合金层剥离现象，而且生产工艺复杂，生产成本高，因此人们开始采用塑料来代替金属材料生产止推垫片，止推垫片功效要求所采用的材料应具有耐摩擦性能好、螨变小、适合高速运转、耐温性好且力学强
度高等特点。南京塑料二厂[2]采用填充聚四氟乙烯(PTFE)制备止推垫片，来取代进口制品。该厂技术人员选定添加碳纤维增强PTFE配方，该产品能代替日本进口产品，技术上达到国内先进水平。 Solvay高级聚合物公司生产的AT-6130HS含30% 玻璃纤维增强的高伸长率聚邻苯二甲酰亚胺(PPA) 树脂，用于生产自动变速箱内的止推垫片。由通用
*浙江省教育厅访间工程师项目(FG2014094)
联系人：杨培娟，讲师，主要从事汽车材料和应用技术研究收稿日期：2015-08-22