Erosão por impacto de partículas caracterização e simulação da ocorrência de Bandas de Cisalhamento Adiabático (ASB) em aço inoxidável duplex UNS S32205

Abstract

The present work describes numerical simulations of surface erosion of a UNS S32205 duplex stainless steel by impact particles. In experiments, the SEM images were used to identify and characterize, in the sub-surfaces of craters formed in the target material, Adiabatic Shear Bands (ASB), resulting from the dynamic compression processes involved in the impacts. The bands may contribute to crack nucleation and consequent fracture of the material along the band, leading to the separation of the material at the plastic deformation edges of the craters, which would mean mass loss (erosion). In the numerical simulations, the conditions under which these bands were formed were determined by means of the analysis of the stress distributions, plastic deformations and recorded temperatures. Firstly, erosive erosion with spherical, cubic and polyhedral particles was simulated in the finite element software to study the morphology of the eroded surface, and then the conditions of ASB occurrence in specific geometries were simulated. These were developed in conditions as close as possible to those of the experiments. The simulations showed that the software used was effective in reproducing the morphology of the eroded surfaces and in the identification of the conditions of appearance of the ASBs.