Micromechanical simulation of plastic deformation behavior and failure commencement in high silicon bainitic steel after austempering

The plastic deformation and failure initiation of super bainitic steels containing different amount of bainite were analyzed using a real microstructure-based micromechanical finite element method (FEM). Real micrograph of such phase steels obtained by microscope were utilized as the representative volume elements (RVEs) in the micromechanical approach. Ductile mode of failure throughout selected RVE was simulated in term of strain localization for the duration of deformation. Calculations were carried out on the representative volume to numerically analyze the effects of characteristics of every individual constituents phase on the macroscopic mechanical properties of steels regarding their quantitative volumetric amount. The results obtained from simulation were assessed against experimental records and it was determined that the real microstructure-based FEM can predict strength and also ductility of the studied bainitic steels. Furthermore, shear failure mode occurs in all heat treated state of the studied steel which correlate quite well with experimental findings.