定、变载弯曲疲劳钢丝绳失效机理对比研究

为对比揭示定、变载弯曲疲劳钢丝绳断裂机理及磨损演化特性，运用自制钢丝绳弯曲疲劳试验机开展钢丝绳定载、变载弯曲疲劳试验，通过人工拆股统计法和VW-9000系列高速度数码显微系统对比研究钢丝绳断丝分布、断丝数、断口和磨痕形貌等断裂机理，对比分析钢丝绳未断钢丝和断丝的磨痕尺寸演化特性. 结果表明：与钢丝绳定载弯曲疲劳相比，变载弯曲疲劳钢丝绳断丝出现较晚，芯股、螺旋股外层断丝数分别较多、较少，芯股外层钢丝断口挤压变形较大，芯股各层钢丝断口裂纹扩展区占比较低，芯股和螺旋股的各层钢丝磨痕尺寸总体较小，钢丝绳更易达到报废水平.

To comparatively reveal the fracture mechanism and wear evolution characteristics of steel wire ropes under constant-amplitude and variable-amplitude bending fatigue loads, a self-made steel wire rope bending fatigue testing machine was used to conduct constant-amplitude and variable-amplitude bending fatigue tests on steel wire ropes. The fracture mechanisms including broken wire distribution, number of broken wires, fracture morphology and wear scar morphology were comparatively studied via the manual strand disassembly and statistics method and the VW-9000 series high-speed digital microscopy system, and the wear size evolution characteristics of intact and broken steel wires in the wire rope were also comparatively analyzed. The results show that, compared with steel wire ropes under constant-amplitude bending fatigue, the occurrence of broken wires in those under variable-amplitude bending fatigue is delayed. The number of broken wires in the outer layer of the core strand is relatively larger, while that in the outer layer of the helical strand is relatively smaller. The fracture surface of the outer layer steel wires in the core strand exhibits greater extrusion deformation, and the proportion of the crack propagation zone in the fracture surfaces of steel wires at all layers of the core strand is relatively low. The wear scar sizes of steel wires at all layers of both the core strand and helical strand are generally smaller, making the steel wire rope more likely to reach the scrap threshold.

搜集汇总

背景与挑战

背景概述

该数据集研究钢丝绳在定载和变载弯曲疲劳条件下的断裂机理及磨损演化特性，通过实验对比分析两种条件下的断丝分布、断口形貌和磨痕尺寸等关键参数。结果表明，变载条件下钢丝绳的断裂行为与定载条件存在明显差异，且更易达到报废水平。