Simulação de Ensaio de Indentação para filmes finos de CrAlN utilizando o Método dos Elementos Finitos

Abstract

Recently, one of the devices used to improve tribological properties of various materials has been the use of thin films applied to their surface in order to achieve improvements in surface hardness or wear resistance. Therefore, to assess the characteristics of these films, it is very important to evaluate the advantages and disadvantages of their use and one of the experimental techniques has been the instrumented indentation test. However, performing these tests on thin films can be a challenge because of the difficulties in measuring stresses and deformations in such a small layer, requiring sophisticated and expensive equipment. Thus, an alternative that emerges to evaluate the behaviour of not only the film, but also the conjugate formed by the film and the substrate, has been numerical simulation, more specifically Finite Element Method (FEM). The main of this study was to simulate the spherical indentation test in a conjugate composed of a thin film of Aluminium Chromium Nitride (CrAlN) deposited on a carbon steel substrate (AISI4140) in order to evaluate the behaviour of its stress field deformations. Finally, the fracture processes that occur in these conjugates were also evaluated. The obtained results were compared with experimental and numerical values existing in the specialized literature.