Image-based Calculation of Stress-strain Curve of the Two-phase Microstructure on the Basis of the Modified Secant Method

Abstract

The secant method proposed by Weng is a practical calculation method to evaluate the stress-strain curve of the two-phase materials, but the shape of the inclusion phase has been often assumed to be a sphere or an ellipsoid in the calculation. In this study, we proposed the modified secant method which is able to calculate the stress-strain curves of the two-phase composite materials including the microstructure with arbitrary morphology, and applied this method to the conventional microstructures in steels, i.e., the ferrite-pearlite and the ferrite-bainite two-phase microstructures.