润滑状态及预紧力对镀达克罗紧固件防松和耐蚀性能的影响  

Influence of Lubricating States and Pre-Clamping Force on the Anti-Loosening and Corrosion Resistance of Dacromet Plated Fasteners

作　　者：郭扬洋 李献杰 李拥军 招晶鑫 淡振华 GUO Yangyang;LI Xianjie;LI Yongjun;ZHAO Jingxin;DAN Zhenhua(College of Materials Science and Engineering,Nanjing Tech University,Nanjing 211816,China;CRRC Nanjing Puzhen Co.,Ltd.,Nanjing 210031,China)

机构地区：[1]南京工业大学材料科学与工程学院,江苏南京211816 [2]中车南京浦镇车辆有限公司,江苏南京210031

出　　处：《材料保护》2025年第3期80-86,共7页Materials Protection

基　　金：国家重点研发计划(2022YFB3705500);国家自然基金(52371157)。

摘　　要：紧固件松动对地铁等轨道交通安全性有重要影响。针对GB/T 5782、M16×80、10.9级镀达克罗六角紧固螺栓的防松性能问题,通过横向振动防松实验及中性盐雾试验,探究了紧固过程的紧固件润滑状态对其防松性能、磨损行为和耐蚀性能的影响。结果表明,当预紧力设置为76 kN时,无润滑紧固件振动1500次剩余预紧力在初始预紧力的95%以上,防松性能优良。涂抹润滑剂会使镀达克罗紧固件防松性能大幅度衰减。当预紧力设置为76、93、110 kN时,有润滑紧固件振动1500次后剩余预紧力均在初始预紧力的8%以下。当预紧力设置为110 kN时,有润滑紧固件振动200次后的剩余预紧力平均在初始预紧力的76.19%,高于76 kN和93 kN时的情况,但后期剩余预紧力并无太大差异。润滑剂在振动过程中将螺纹表面的固固摩擦转化为固液摩擦,相对摩擦力大幅度下降。无润滑时紧固件并无松动,镀层破坏较轻,镀层通过锌离子的牺牲阳极法足以保护基体不受盐雾腐蚀,而润滑剂会使得螺栓松动,螺母与螺纹产生较大的相对运动,其摩擦力破坏表面镀层,露出紧固件碳钢基体,使得其在盐雾条件下发生腐蚀。The loosening of fasteners has an important impact on the safety of subway and other rail transit.Aiming at the anti-loosening performance of GB/T 5782,M16×80,10.9 class Dacromet plated hexagon fastening bolts,the effects of lubrication state of fasteners on anti-loosening performance,wear behavior and corrosion resistance were investigated through lateral vibration anti-loosening test and neutral salt spray test.Results showed that when the preload force was set to 76 kN,the residual preload force of non-lubricated fasteners was more than 95%of the initial preload force for 1500 vibration times,and the anti-loosening performance was excellent.Meanwhile,the anti-loosening performance of dacromet plated fasteners would be greatly attenuated by applying lubricants.When the preload force was set to 76,93,110 kN,the remaining preload force after 1500 vibration of the lubricated fasteners was less than 8%of the initial preload force.When the preloading force was set to 110 kN,the average residual preloading force after 200 times of vibration of the lubricated fasteners was 76.19%of the initial preloading force,which was higher that at 76 kN and 93 kN,but the residual preloading force of the late surface was not much different.In the process of vibration,the solid friction of the thread surface was transformed into solid liquid friction,and the relative friction was greatly reduced.When there was no lubrication,the fasteners were not loose,and the coating damage was light.Furthermore,the coating could protect the substrate from salt spray corrosion by sacrificial anode method of zinc ion,while the lubricant would loosen the bolts and produce a large relative movement between nuts and threads.The friction could destroy the surface coating and expose the carbon steel substrate of the fastener,causing corrosion under the condition of salt spray.

关 键 词：镀达克罗螺栓 横向振动 润滑剂 盐雾腐蚀试验 

分 类 号：TG174[金属学及工艺—金属表面处理]