中文摘要：

利用自制的一套真空低温超声马达摩擦驱动特性测试系统，选取了4种工程塑料作为超声马达转子摩擦材料，测试出超声马达在真空低温环境下的空载转速，研究了真空度、环境温度和摩擦材料等因素对行波超声马达空载特性的影响．结果表明，随着真空度的增加，马达的空载转速下降；随着环境温度的降低，马达的空载转速下降．比较了所选4种工程塑料的驱动特性，筛选出一种在真空低温环境下空载特性较好的超声马达转子摩擦材料．

英文摘要：

The no - load speed of ultrasonic motor （USM） with different friction materials of four selected engineering plastics was measured by using testing system of friction drive characteristics of USM under vacuum and low temperature. The effects of vacuum degree, environmental temperature and friction materials on no - load properties of traveling wave ultrasonic motor were researched. The results show that the no - load speed of ultrasonic motor decreased with the increase of vacuum degree and decrease of environmental temperature. The friction materials which is suitable for vacuum and low temperature was found by comparing the drive properties of the four engineering plastics.