Influence of fatigue loading on the residual stress induced by cold drawing in prestressing steels

Resumo

Nowadays, cold drawing is the main conforming process used in industry for obtainingprestressing steel wires which are commonly subjected to fatigue loading during their life in-service. Plasticstrain generated during wire drawing produces undesirable residual stresses which can affect the structuralintegrity of the material in both inert and aggressive environments. So, it seems to be interesting to analysethe evolution during several fatigue loading schemes of diverse residual stress states similar to the onesproduced after a cold drawing process. To achieve this goal, numerical simulations by finite elementmethod were carried out applying diverse fatigue loading schemes to several cold drawn prestressing steelwires. For each one of them a residual stress state was introduced, some of them with a tensile state at thewire surface and others with a compressive state. On one hand, numerical results reveal the key role ofplastic strains produced by fatigue loading causing a redistribution of the wire residual stress when tensilestresses are placed at the wire surface. On the other hand, results show a negligible effect of fatigueloading on the residual stress state of those wires where a compressive residual stress was considered.