同步器系统的粉末冶金零件

P/M components for synchronizer systems

近年来,手动变速器的同步器系统中的关键零件,诸如同步器齿毂与同步器锁环,都在用粉末冶金工艺大量生产。本文首先介绍近年来生产先进同步器齿毂用的高强度粉末冶金钢;然后对碳纤维、烧结摩擦层及Mo丝喷涂衬面3种同步器锁环用摩擦衬面进行了比较,根据压力与滑动速度讨论了其摩擦性能与寿命长短;最后,特别强调了粉末冶金的新发展,诸如滑动齿套与负载齿轮,给出并讨论了滑动齿套的应用试验结果,阐述了表面致密化螺旋齿轮的使用性能,给出了运转-时间试验的结果,并和常规的锻钢齿轮进行了比较。

During the past years, key components for synchronizing systems in manual transmission gear boxes such as synchronizer hubs and synchronizer rings have been manufactured in large quantities by P/M technology. After presenting recent developments in high strength P/M steels for advanced synchronizer hubs, this paper compares three frictional linings for synchronizer rings based on carbon-fabric, sintered friction layers and molybdenum wire-sprayed linings. Results on friction performance and life time tests are discussed in terms of pressure and sliding speed. Finally, special emphasis is given to new P/M developments such as sliding sleeves and load bearing gears. Application test results for sliding sleeves are described and discussed with respect to field test results. Eventually, the performance of surface densified helical P/M gears is outlined. Results obtained from run-time tests are presented and compared to standard wrought steel gears.