Análise numérica da indentação dinâmica de materiais elasto-viscoplásticos revestidos

Abstract

Two issues of great importance in today’s aerospace industry are collision with debris in the space environment and the high temperatures to which re-entry capsules are exposed. For both cases, there are solutions related to the application of a coating on risk components, justifying the great importance of the mechanical characterization of coated specimens. Furthermore, for the two cited applications, the observed velocities are quite high, leading to the need to consider their effects during the design phases. A very common method to carry out the characterization of engineering materials is the indentation tests, the dynamic ones being indicated for cases where the indentation rate has relevance. Due to the high complexity of carrying out tests of this type, as well as the difficulty in obtaining analytical solutions for the problem, it becomes very interesting to carry out simulations to characterize the materials. Thus, the present work aims to carry out numerical analyzes of the indentation process of coated elasto-viscoplastic materials. The simulations were performed using the finite element method, where the commercial software Abaqus was used. To understand the influence of parametric variations on the behavior of the specimen, alterations were made in the thickness, modulus of elasticity and yield stress of the coating, as well as changes in the indentation speed. Based on the analyses, the loading curves vs. depth of indentation, as well as stress fields and accumulated plastic strain were evaluated