Abstract Two ways to enhance conversion efficiency of the ultrasonic motor (USM) were developed. According to mechanical and tribological properties, an advanced polyimide (PI) friction material was fabricated. In comparison to conventional polytetraflfluoroethylene (PTFE) friction material, the novel PI friction material enhanced efficiency from 29% to 44%, an improvement of 51.7%. The results indicated high friction coefficient and high elastic modulus were essential for improving efficiency. Inspired by the unique topography, the micro-dimples were introduced into PI friction material which improved the efficiency from 44% to 53%, an increment of 20.5%. The optimum parameter was diameter of 200 μm and area density of 7%. The effect of surface texture on tribological behavior and output characteristic of the USM was comprehensively explored.

中文翻译：

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用于提高超声波电机转换效率的表面织构聚酰亚胺复合材料

摘要 开发了两种提高超声电机（USM）转换效率的方法。根据机械和摩擦学性能，制造了一种先进的聚酰亚胺 (PI) 摩擦材料。与传统的聚四氟乙烯（PTFE）摩擦材料相比，新型PI摩擦材料的效率从29%提高到44%，提高了51.7%。结果表明，高摩擦系数和高弹性模量对于提高效率至关重要。受独特地形的启发，微凹坑被引入到PI摩擦材料中，将效率从44%提高到53%，增加了20.5%。最佳参数为直径为 200 μm，面积密度为 7%。全面探讨了表面纹理对 USM 摩擦学行为和输出特性的影响。