Characterization on stress-strain behavior of ferrite and austenite in a 2205 duplex stainless steel based on nanoindentation and finite element method

The stress-strain behavior of ferrite and austenite in a commercial 2205 duplex stainless steel was investigated by using nanoindentation test and microstructure-based finite element method (FEM). Results showed that the optimum load range for measuring phase properties in nanoindentation test was from 3000 mu N to 7000 mu N. The ferrite has slightly higher average elastic modulus than austenite, while austenite has higher average nano-hardness than ferrite. Representative stress-strain curves of ferrite and austenite were determined by means of the power-law hardening and empirical relationship. Based on FEM, the differences in distribution and portion of stress-strain in local phases were visualized, and the overall flow curve of the sample 2205 was extracted, which was in good agreement with the obtained results from uniaxial tensile experiment.