新型高效钢背/自润滑复合材料衬层结构传动螺母

A Novel Type of Transmission Screw Nuts with Structure of Steel Backing/Self-lubricant Composite Lining

为克服传统传动滑动螺旋副摩擦因数大、效率低的缺点,提出一种带衬层螺母的创新方案:螺母以钢为基体,衬层为碳纤维织物增强聚合物自润滑复合材料,兼有高的承载能力和低的摩擦因数。研究自润滑复合材料的配方、制备工艺、减摩机理和摩擦学性能。衬层表面的织构形成微润滑池,固-液协同润滑改善了重载下的润滑效果;衬层采用成形加工并在表面形成润滑油道,进一步改善了润滑条件。开发了新型螺旋副的制备工艺并研制了630 kN压力机实用螺母,测试表明,新型螺母较ZCuSn10Pb1青铜螺母的工作性能有较大提高,重载条件下复合材料螺母摩擦因数降低了21.2%,而传动效率提高了10.6%。新型螺旋副的开发,不仅解决了伺服压力机的发展的一个瓶颈问题,而且对于所有采用螺旋传动的机械装备都具有重要的意义。

A novel type of screw transmission is put forward to solve the problem of high friction coefficient and low efficiency for sliding screw pairs. The nuts are characterized by steel backing and a lining made of carbon fabric reinforced self-lubricant composite material on female thread surfaces. The formulation, preparation, tribological properties and mechanism of lining material are studied. Micro-lubricant-pools are formed on lining surface texture and the synergistic effects of oil and solid lubricants in the pools improved the lubrication greatly. The spiral lining is molded and the lubrication grooves on the surface are also implemented to improve lubrication further. The fabricating processes of the nuts are studied and a nut for a 630 kN press is made. The experiments showed that the composite nut exhibited excellent friction properties under heavy-duty condition. Frictional coefficient of the composite nut decreased by 21.2% and transmission efficiency increased by 10.6% in comparison with bronze ZCu Sn10Pb1 nut. The development of new type of sliding screw-nuts can not only promote the development of servo presses, but also possess a great significance to all the mechanical equipments with screw-transmission.