A Reverse Method Based Approach for Evaluating the Local Stress-Strain Curves of Metallic Materials from Instrumented Indentation
Résumé
In this presentation, we propose an approach to estimate the local stress–strain characteristics of metallic materials from instrumented indentation data. This approach is based on a reverse method which imply to first perform a set of numerical indentations. Contrary to inverse methods, the generated analytical reduced model can then be used to instantaneously evaluate the desired local properties from experimental instrumented indentation curves. In order to improve the estimation accuracy, it is able to take into account the elastic deformations of the indenter occurring during the test. It is also able to take into account the defect in shape of the actual indenter. This proposed general approach has been applied in the particular case of linear hardening behaviour. This approach were then successfully validated by comparison with experimental tensile test results. Finally it has been used to estimate the local tensile curves in various projects, such as the local characterisation of welded joints to be treated by high frequency hammer peening.