저자명 M. Kim and H. Huh 
Name WCCM2016 
Place WCCM2016 
Year 2016 
This paper is concerned with the hardening behavior of sheet metals at intermediate strain rates ranging from 0.001 s-1 to 100 s-1 with respect to the pre-strain in order to propose a new flow stress model for a pre-strained material. Most members of an auto-body are made of mild steels or advanced high strength steels(AHSS) fabricated by the sheet metal forming process. During the process, the flow stress of the sheet metals are changed with the plastic strain as well as residual stress and consequently the tensile properties of the sheet metals are also changed. A new design of a device to impose the pre-strain was developed to investigate the hardening behavior of the sheet metals considering the pre-strain and the specimens were obtained from the sheet metals with SPCC(CQ) and DP590(DP) for outer and inner members of an auto-body. The specimens were prepared with the pre-strain of 5 % and 10 % using tensile testing machines and the pre-straining device. The Instron 5583 and a high speed material testing machine (HSMTM) were utilized at the quasi-static state of 0.001 s-1 and the intermediate strain rates ranging from 1 s-1 to 100 s-1 respectively. The experimental results demonstrate that the stress–strain curves at the strain rate of 0.001 s-1 for SPCC and DP590 pre-strained by 5 % and 10 % traced the original stress–strain curve without the pre-strain, following a classical conjecture that the flow stress of a material follows the unique stress–strain curve. The results also reveal that the hardening behavior of SPCC and DP590 were noticeably influenced by the pre-strain with stress overshooting when the strain rate is over 1 s-1 and the flow stress as well as the ultimate tensile strength increased due to the pre-strains consequently. For an accurate crash analysis of an auto-body, the correct material properties should be utilized for the numerical simulation with the stress–strain relation depending on the strain rate and the amount of pre-strain.
번호 제목 저자명 날짜 조회 수
16 Tensile Properties of Auto-body Plastic with Various Strain Rates for FEM by Using The DIC Method and The Force Equilibrium Grid Method file Jesung Yoo, Hoon Huh,...  2017.06.07 205
15 AN IMPROVED DEVICE FOR THE TENSION/COMPRESSION TEST AT INTERMEDIATE STRAIN RATES file Geunsu Joo, Hoon Huh  2017.06.07 213
14 ASYMMETRIC MECHANICAL PROPERTIES OF TRIP980 AND TWIP980 STEEL SHEETS AT VARIOUS STRAIN RATES file Geunsu Joo, Hoon Huh  2017.06.07 217
13 RATE-DEPENDENT HARDENING BEHAVIORS OF ULTRA-HIGH STRENGTH STEEL SHEETS UNDER IN-PLANE TENSION/COMPRESSION file Hoon Huh, Geunsu Joo  2017.06.07 231
12 Rate-dependent Material Parameters of the Combined Isotropic/kinematic Hardening Model for the TRIP980 steel sheet file Geunsu Joo, Hoon Huh  2017.06.07 216
11 Prediction of the Ductile-to-Brittle Transition Temperature of a silicon steel under various strain rate conditions file Junbeom Kwon, Hoon Hu...  2017.06.07 210
10 Evaluation of tensile properties of heat-treated AISI4340 steel at various strain rates file N. Park, S.J. Lim, an...  2017.06.07 216
9 Prediction of the onset of fracture of DP980 steel 1.2t under typical loading conditions based on associated and non-associated flow rules file N. Park and H. Huh  2017.06.07 216
8 A Method for Evaluation of Tensile Properties of a Nugget Zone in a Spot-Welded Joint Considering the Strain Rate N. Park, M. Park, and...  2017.06.07 210
7 Tensile properties of a tempered glass plate at the quasi-static state M. Kim, H. Huh, E. Ju...  2017.06.07 202
» Investigation of the hardening behavior of sheet metals at intermediate strain rates considering the pre-strain M. Kim and H. Huh  2017.06.07 303
5 Prediction of fracture initiation in square cup drawing of DP980 using an anisotropic ductile fracture criterion file N. Park, H. Huh, J. Yoon  2017.10.11 86
4 Effect of Pre-strain on Tensile Properties of Al5052-H32 under an Electropulsing Condition M. Kim, J. Song, H. Huh  2017.10.11 81
3 Modeling of rate-dependent hardening behaviors of the TWIP980 steel sheet in tension and compression file Geunsu Joo, Hoon Huh  2017.10.11 77
2 Validation of the Thermal Softening Effect at a Wide Range of Strain Rates by Using the Taylor Impact Test file MingJun Piao, Hoon Hu...  2017.10.11 109
1 Characterization of Hardening Behavior at Ultra-High Strain Rate, Large Strain, and High Temperature file MingJun Piao, Hoon Hu...  2017.10.11 114