SKF公司已经开发出了一些铁路牵引电机用的陶瓷 (氮化硅 )滚珠复合轴承。陶瓷滚珠比钢质的轻40 % ,允许轴承在较低温度下工作 ,磨损小 ,少维修。随着牵引电机的高速化 ,传统的油脂润滑钢珠已不能满足使用者对延长使用周期 ,即降低运转期间费用的要求。同时 ,随着三相技术的采用 SKF has developed ceramic (silicon nitride) ball bearings for railway traction motors. Ceramic balls are 40% lighter than steel, allowing bearings to work at lower temperatures with less wear and less maintenance. With the high-speed traction motor, the traditional grease-lubricated steel ball can not meet the user to extend the use of the cycle, that is, reducing the cost of operation requirements. At the same time, with the adoption of three-phase technology