The influence of combined corrosion and vibration to the anti-loosening performance of a precision locknut used in a machine tool is investigated. Firstly, the locknut was submerged in 5% NaCl solution according to ASTM B895 standard for corrosion testing. The locknuts, after submerged in 1-hr, 2-hr and 4-hr periods, respectively, were then installed on the rotating spindle in a vertical dynamic impact tester for performing anti-loosening test. The initial installed pretension was 9800 N and the spindle was rotating in a constant speed of 1000 rpm. Turmogrease Li 802 EP lubricant was used on the contact surface between spindle thread and locknut. The set screws on the locknut were tightened sequentially and evenly in three-stage of torque: 1.96 N-m, 3.92 N-m and 5.88 N-m. Its real-time pretension variation with the periodic transverse impact and its final loosening torque were measured. Accordingly, the axial force ratio and anti-loosening torque ratio were calculated and discussed. It was found that corrosion treatment had similar influence on both the axial force ratio and the anti-loosening torque ratio. More corrosion on the locknut with longer submersion in NaCl solution deteriorated its anti-loosening characteristics. The result could serve as the reference for evaluating the fastening performance of precision locknut and guide the design and manufacturing for the application improvement.

研究了腐蚀和振动相结合对机床所用精密防松螺母的防松性能的影响。首先，根据ASTM B895标准，将防松螺母浸入5％NaCl溶液中进行腐蚀测试。将防松螺母分别浸入1小时，2小时和4小时后，然后将其安装在立式动态冲击测试仪中的旋转主轴上，以进行防松脱测试。初始安装的预张力为9800 N，主轴以1000 rpm的恒定速度旋转。Turmogrease Li 802 EP润滑剂用于主轴螺纹和防松螺母之间的接触表面。依次并均匀地以三个阶段的扭矩拧紧防松螺母上的定位螺钉：1.96 Nm，3.92 Nm和5.88 Nm。测量了其随周期横向冲击的实时预紧力变化以及最终的松弛扭矩。因此，计算并讨论了轴向力比和防松扭矩比。发现腐蚀处理对轴向力比和抗松动扭矩比具有相似的影响。长时间浸入NaCl溶液中的防松螺母受到的腐蚀越严重，其防松性能就越差。该结果可作为评估精密防松螺母紧固性能的参考，并为改进应用提供指导。发现腐蚀处理对轴向力比和抗松动扭矩比具有相似的影响。长时间浸入NaCl溶液中的防松螺母受到的腐蚀越严重，其防松性能就越差。该结果可作为评估精密防松螺母紧固性能的参考，并为改进应用提供指导。发现腐蚀处理对轴向力比和抗松动扭矩比具有相似的影响。长时间浸入NaCl溶液中的防松螺母受到的腐蚀越严重，其防松性能就越差。该结果可作为评估精密防松螺母紧固性能的参考，并为改进应用提供指导。