磨损活塞杆化学复合镀修复工艺

Reparation process of worn piston rod by electroless composite plating

应用化学复合镀技术修复磨损的作动筒活塞杆,介绍了化学复合镀Ni–P–PTFE(聚四氟乙烯)镀液配方、修复工艺流程及工艺条件。讨论了温度、pH、搅拌方式对PTFE复合量的影响,获得了化学复合镀较佳的工艺条件:温度85～95°C,pH=4.8,机械搅拌10min、间歇1min。修复层测试结果表明,镀层厚度为20μm的修复件,其显微硬度为390HV,使用3个月后的磨损量为1.2g。修复件的使用寿命达到3年,满足用户要求。

The worn actuator piston rod was repaired by electroless composite plating. The bath formulation of electroless composite Ni-P-PTFE （polytetrafluoroethylene） plating, reparation process flow and technological conditions were introduced. The effects of temperature, pH and stirring method on the amount of PTFE incorporated were discussed. The optimal process conditions were obtained as follows： temperature 85-95 ℃, pH 4.8 and mechanical stirring 10 rain followed by intermission of 1 min. The test results of repaired deposits showed that the deposit with a thickness of 20 μm has a microhardness of 390 HV and its wear loss is 1.2 g after use for three months. The service life of workpiece after reparation is up to three years and thus meets users＇ requirements.