扭矩作用下垂向载荷对转轴表面微动损伤特性的影响

Effect of Vertical Load on Fretting Damage Characteristic of Shaft Surface in Torsion

利用JD-1型轮轨模拟试验机研究了在扭矩作用下转轴表面的微动损伤,通过改变垂向载荷大小,研究了垂向载荷对转轴与轴承内圈过盈配合面微动损伤特性的影响,并借助激光共聚焦扫描电镜和扫描电子显微镜观察了损伤表面的磨痕和剖面的显微组织,分析了两种垂向载荷下转轴表面的微动损伤机理。结果表明:在垂向载荷作用下,转轴与左右两端轴承内圈过盈配合面处出现了微动损伤,磨损形式主要表现为黏着磨损和磨粒磨损;在垂向载荷较大的工况下,转轴配合面的表面磨损加剧,塑性变形层变厚,微动损伤变得更严重,并且左端配合面的磨损和塑性变形均比右端的严重,塑性变形层的厚度分布更加不均。

Fretting damage on shaft surface in torsion was studied by using JD-1 wheel/rail simulation tester, and the effect of vertical load on fretting damage characteristic of interface fit between shaft and inner surface of bearings was investigated. The fretting damage mechanism of shaft surface was analyzed by observing the surface wear scar and microstructure of cross section of specimens by using laser scanning confocal microscopy and scanning electronic microscopy. The results indicate that the fretting damage appeares on the interface fit between shaft and inner surface of bearings at vertical loads, the wear is mainly in the form of adhesive wear and abrasive wear. Under higher vertical load condition, the wear on the surfaces of shaft is more serious, plastic layers in the interface fit both become thicker, the fretting damage becomes severer, moreover, the wear and plastic deformation on the left surface are severer than those on the right surface, and the thickness of the plastic layer is uneven.