HOME > Publications > Korean Conferences
Prediction of Fracture Strains for DP980 Steel Sheets at a Wide Range of Loading Paths
2014.10.29 10:40
| 저자명 | N. Park, H. Huh |
|---|---|
| Name | 2014 KSTP fall conference |
| Year | 2014 |
| page |
This paper is concerned
with prediction of fracture strains for DP980 steel sheets at a wide range of
loading paths. The usage of DP980 steel is significantly increasing in
automotive industries for enhanced safety and high fuel efficiency. The
material behavior of advanced high-strength steels (AHSSs) sheets show
unpredictable and sudden fracture in sheet metal forming processes. A modified
Lou–Huh ductile fracture
criterion is utilized to predict the formability of AHSSs because the
conventional forming limit diagram (FLD) constructed based on necking is unable
to evaluate the formability of AHSSs. Fracture loci were extracted from three
dimensional fracture envelopes by assuming the plane stress condition to
evaluate equivalent plastic strains at the onset of fracture at a wide range of
loading paths. Three different types of specimens such as pure shear, dog-bone
and plane strain grooved specimens were utilized for tensile tests to calibrate
the fracture model of DP980 steel sheets. Fracture strains of each loading path
were evaluated to show that there is little deviation between fracture strains
predicted from the fracture model and experimentally acquired ones. Through the
comparison, it is clearly shown that the three dimensional fracture envelopes
can accurately predict the onset of the fracture of DP980 steel sheets in
complicated loading conditions from compressive loading, and shear to
equi-biaxial tension.
