Ductile fracture behavior of higher grade dual phase (DP) steels is observed to be quite different from the typical ductile fracture of mild steel and high strength low alloy (HSLA). In this paper, the approximate range of martensite volume fraction where the microstructure-level phase inhomogeneity may have dominant effects on the overall deformation/failure behavior of DP steels is determined using the microstructure-based modeling approach. For this purpose, various finite element models with different martensite volume fractions are first developed, and then the effects of the ductility of ferrite phase and the voids on the overall ductility of DP steels are examined. The results indicate that, when martensite volume fraction in DP steels exceeds about 15%, the microstructure-level phase inhomogeneity becomes the key factor dominating the ductile fracture of DP steels.
Revised: September 20, 2016 |
Published: November 1, 2009
Citation
Choi K., A. Soulami, W.N. Liu, X. Sun, and M.A. Khaleel. 2009.Fracture Driven by Phase Inhomogeneity in Higher Grade Dual Phase Steels. In International Automotive Body Congress (IABC 2009), November 4-5, 2009, Troy, Michigan, 464-469. Ann Arbor, Michigan:Global Powertrain Congress.PNNL-SA-69013.