Mechanical and Wear Behavior of Steel Wires in Typical Contact Area Under Tension-tension Fatigue

Abstract

In this study, the issues of the complex mechanical behavior inside steel wire rope and wear evolution of internal wire at typical contact areas where the fracture of the wire is more likely to occur is particularly considered. First, the fretting parameters of steel wires at typical contact areas were calculated. Then the wear evolution process under tensile loads with different stress ratios was simulated by using the finite element method (FEM) based on the calculated parameters. Finally, the micro-morphology and element concentration and distribution of wear scars at typical contact areas were observed. The results demonstrate that: (1) The relative displacement value and normal contact stress between the outer layer steel wires of core strand and outer strands are maximum, which cause the most severe wear in this area. As the stress ratio decreases from 0.5 to 0.25, the fretting parameters of steel wires increase. (2) The wear evolution process is divided into running-in stage and stable wear stage, which are characterized by the rapid decline and stabilization of wear rate, respectively. (3) Compared with other contact areas, the concentration of iron, carbon and chlorine in the contact area between strands is obviously higher. Meanwhile, there exist strong plastic deformation, severe delamination and primary and secondary cracks in this region, resulting in stress concentration and thus the fatigue life decrease of steel wire.