横向交变载荷下TiCN/MoS2涂层螺栓的防松性能研究

基于自主设计的螺栓连接振动试验装置，系统研究了横向交变载荷下TiCN/MoS₂涂层螺栓分别与TiCN/MoS₂涂层螺母和无涂层螺母配合时连接结构的松动行为，并利用体式显微镜(OM)、扫描电子显微镜(SEM)、电子能谱仪(EDX)和白光干涉仪等微观分析设备对试验后的螺纹表面进行损伤分析，深入讨论其磨损机理. 结果表明:在相同试验条件下，TiCN/MoS₂涂层螺栓比无涂层螺栓螺纹表面的损伤轻微，连接结构的松动程度更低；与无涂层螺栓螺纹根部相同等效应力状态下，TiCN/MoS₂涂层螺栓连接结构的预紧力可提高约10%，螺纹表面的损伤减轻，同时连接结构的松动程度进一步降低；TiCN/MoS₂涂层螺栓螺纹表面的主要磨损机制为疲劳磨损. 

Anti-Loosening Performance of the TiCN/MoS2 Coated Bolts under Transverse Alternating Load

Based on the self-designed testing equipment for bolted joints, the self-loosening behaviour of the TiCN/MoS₂ coated bolts, which were connected with the TiCN/MoS₂ coated nuts and the uncoated nuts respectively, was systematically studied under transverse alternating load. After tests, the morphologies of the damaged threads were analyzed using three-dimensional microscope, scanning electron microscope, energy dispersive X-ray and white light interferometer. Furthermore, the wear mechanisms were investigated on the first thread surfaces. The results showed that the thread damage of the TiCN/MoS₂ coated bolts was slighter than that of the uncoated bolts, and the self-loosening degree of the TiCN/MoS₂ coated bolts was lower than that of the uncoated bolts under the same experimental parameters. Moreover, under the same equivalent stress as that of the uncoated bolts at the thread root, the preload of the TiCN/MoS₂ coated bolt can be improved by about 10%, the damage of the thread surface was further reduced, and the self-loosening degree of bolted joints was also decreased. In addition, delamination was the main wear mechanism on the first thread surface of the composite coated bolts.