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Title: On Key Factors Influencing Ductile Fractures of Dual Phase (DP) Steels

Abstract

In this paper, we examine the key factors influencing ductile failure of various grades of dual phase (DP) steels using the microstructure-based modeling approach. Various microstructure-based finite element models are generated based on the actual microstructures of DP steels with different martensite volume fractions. These models are, then, used to investigate the influence of ductility of the constituent ferrite phase and also the influence of voids introduced in the ferrite phase on the overall ductility of DP steels. It is found that with volume fraction of martensite in the microstructure less than 15%, the overall ductility of the DP steels strongly depends on the ductility of the ferrite matrix, hence pre-existing micro voids in the microstructure significantly reduce the overall ductility of the steel. When the volume fraction of martensite is above 15%, the preexisting voids in the ferrite matrix does not significantly reduce the overall ductility of the DP steels, and the overall ductility is more influenced by the mechanical property disparity between the two phases. The applicability of the phase inhomogeneity driven ductile failure of DP steels is then discussed based on the obtained computational results for various grades of DP steels, and the experimentally obtained scanning electronmore » microscopy (SEM) pictures of the corresponding grades of DP steels near fracture surface are used as evidence for result validations.« less

Authors:
; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
972965
Report Number(s):
PNNL-SA-67936
VT0505000; TRN: US201005%%475
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Science and Engineering. A. Structural Materials: Properties, Microstructure and Processing, 526(1-2):140-149; Journal Volume: 526; Journal Issue: 1-2
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; DUCTILITY; FERRITE; FRACTURES; MARTENSITE; MICROSTRUCTURE; SCANNING ELECTRON MICROSCOPY; SIMULATION; STEELS

Citation Formats

Sun, Xin, Choi, Kyoo Sil, Soulami, Ayoub, Liu, Wenning N., and Khaleel, Mohammad A. On Key Factors Influencing Ductile Fractures of Dual Phase (DP) Steels. United States: N. p., 2009. Web. doi:10.1016/j.msea.2009.08.010.
Sun, Xin, Choi, Kyoo Sil, Soulami, Ayoub, Liu, Wenning N., & Khaleel, Mohammad A. On Key Factors Influencing Ductile Fractures of Dual Phase (DP) Steels. United States. doi:10.1016/j.msea.2009.08.010.
Sun, Xin, Choi, Kyoo Sil, Soulami, Ayoub, Liu, Wenning N., and Khaleel, Mohammad A. 2009. "On Key Factors Influencing Ductile Fractures of Dual Phase (DP) Steels". United States. doi:10.1016/j.msea.2009.08.010.
@article{osti_972965,
title = {On Key Factors Influencing Ductile Fractures of Dual Phase (DP) Steels},
author = {Sun, Xin and Choi, Kyoo Sil and Soulami, Ayoub and Liu, Wenning N. and Khaleel, Mohammad A.},
abstractNote = {In this paper, we examine the key factors influencing ductile failure of various grades of dual phase (DP) steels using the microstructure-based modeling approach. Various microstructure-based finite element models are generated based on the actual microstructures of DP steels with different martensite volume fractions. These models are, then, used to investigate the influence of ductility of the constituent ferrite phase and also the influence of voids introduced in the ferrite phase on the overall ductility of DP steels. It is found that with volume fraction of martensite in the microstructure less than 15%, the overall ductility of the DP steels strongly depends on the ductility of the ferrite matrix, hence pre-existing micro voids in the microstructure significantly reduce the overall ductility of the steel. When the volume fraction of martensite is above 15%, the preexisting voids in the ferrite matrix does not significantly reduce the overall ductility of the DP steels, and the overall ductility is more influenced by the mechanical property disparity between the two phases. The applicability of the phase inhomogeneity driven ductile failure of DP steels is then discussed based on the obtained computational results for various grades of DP steels, and the experimentally obtained scanning electron microscopy (SEM) pictures of the corresponding grades of DP steels near fracture surface are used as evidence for result validations.},
doi = {10.1016/j.msea.2009.08.010},
journal = {Materials Science and Engineering. A. Structural Materials: Properties, Microstructure and Processing, 526(1-2):140-149},
number = 1-2,
volume = 526,
place = {United States},
year = 2009,
month =
}
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