0
Research Papers

Introduction to a Third-Generation Automobile Steel and Its Optimal Warm-Stamping Process

[+] Author and Article Information
Ying Chang

School of Automotive Engineering,
National Key Laboratory of Industrial Equipment
Structural Analysis,
Dalian University of Technology,
Dalian 116024, China

Cunyu Wang, Han Dong

East China Branch of Central Iron & Steel
Research Institute (CISRI),
Beijing 100081, China

Kunmin Zhao

School of Automotive Engineering,
National Key Laboratory of Industrial Equipment
Structural Analysis,
Dalian University of Technology,
Dalian 116024, China
e-mail: kmzhao@dlut.edu.cn

Jianwen Yan

Industrial and Equipment Technology Institute,
Hefei University of Technology,
Hefei 230601, China

1Corresponding author.

Contributed by the Manufacturing Engineering Division of ASME for publication in the JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING. Manuscript received June 13, 2015; final manuscript received September 14, 2015; published online October 27, 2015. Assoc. Editor: Wayne Cai.

J. Manuf. Sci. Eng 138(4), 041010 (Oct 27, 2015) (7 pages) Paper No: MANU-15-1284; doi: 10.1115/1.4031636 History: Received June 13, 2015; Revised September 14, 2015

The medium-Mn steel is a promising third-generation automobile steel. Its chemical composition, microstructure, and thermal and mechanical properties are introduced and a warm-stamping process for the medium-Mn steel is proposed. The optimal process parameters are identified through the design of experiments (DOE) and range analysis. The evaluated experimental indexes include tensile strength, elongation, and hardness. The optimal forming process consists of an austenitization temperature of 840 °C, a soaking time of 4 min, and an initial stamping temperature of 500 °C. The proposed process was applied to the warm stamping of an automotive B-pillar. The microstructure of ultrafine, uniform, and complete martensite laths was obtained. The formed part exhibits approximately 1420 MPa tensile strength, over 11% elongation and 460 HV hardness. The optimal warm-stamping process has proved effective and applicable for forming medium-Mn steel parts. It will help promote the application of the third-generation automotive steels.

FIGURES IN THIS ARTICLE
<>
Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.

References

Bardelcik, A. , Christopher, P. , Winkler, S. , Wells, M. A. , and Worswick, M. J. , 2010, “ Effect of Cooling Rate on the High Strain Rate Properties of Boron Steel,” Int. J. Impact Eng., 37(6), pp. 694–702. [CrossRef]
Kim, J. T. , Jeon, Y. P. , Kim, B. M. , and Kang, C. G. , 2012, “ Die Design for a Center Pillar Part by Process Analysis of Hot Stamping and Its Experimental Verification,” Int. J. Precis. Eng. Manuf., 13(9), pp. 1051–1057.
Turetta, A. , Bruschi, S. , and Ghiotti, A. , 2006, “ Investigation of 22MnB5 Formability in Hot Stamping Operations,” J. Mater. Process. Technol., 177(1–3), pp. 396–400. [CrossRef]
Merklein, M. , and Lechler, J. , 2006, “ Investigation of the Thermo-Mechanical Properties of Hot Stamping Steels,” J. Mater. Process. Technol., 177(1–3), pp. 452–455. [CrossRef]
Kolleck, R. , Veit, R. , Merklein, M. , Lechler, J. , and Geiger, M. , 2009, “ Investigation on Induction Heating for Hot Stamping of Boron Alloyed Steels,” CIRP Ann. Manuf. Technol., 58(1), pp. 275–278. [CrossRef]
Chang, Y. , Meng, Z. H. , Ying, L. , Li, X. D. , Ma, N. , and Hu, P. , 2011, “ Influence of Hot Press Forming Techniques on Properties of Vehicle High Strength Steels,” J. Iron Steel Res. Int., 18(5), pp. 59–63. [CrossRef]
Zhao, K. M. , Chang, Y. , Hu, P. , and Wu, Y. C. , “ Influence of Rapid Cooling Pretreatment on Microstructure and Mechanical Property of Hot Stamped AHSS Part,” J. Mater. Process. Technol. (in press).
Karbasian, H. , and Tekkaya, A. E. , 2010, “ A Review on Hot Stamping,” J. Mater. Process. Technol., 210(15), pp. 2103–2118. [CrossRef]
Abbasi, M. , Saeed-Akbari, A. , and Naderi, M. , 2012, “ The Effect of Strain Rate and Deformation Temperature on the Characteristics of Isothermally Hot Compressed Boron-Alloyed Steel,” Mater. Sci. Eng. A, 538, pp. 356–363. [CrossRef]
Ikeuchi, K. , and Yanagimoto, J. , 2011, “ Valuation Method for Effects of Hot Stamping Process Parameters on Product Properties Using Hot Forming Simulator,” J. Mater. Process. Technol., 211(8), pp. 1441–1447. [CrossRef]
Liu, H. P. , Lu, X. W. , Jin, X. J. , Dong, H. , and Shi, J. , 2011, “ Enhanced Mechanical Properties of a Hot Stamped Advanced High-Strength Steel Treated by Quenching and Partitioning Process,” Scr. Mater., 64(8), pp. 749–752. [CrossRef]
Shi, J. , Sun, X. J. , Wang, M. Q. , Hui, W. J. , Dong, H. , and Cao, W. Q. , 2010, “ Enhanced Work-Hardening Behavior and Mechanical Properties in Ultrafine-Grained Steels With Large-Fractioned Metastable Austenite,” Scr. Mater., 63(8), pp. 815–818. [CrossRef]
Wang, C. Y. , 2010, “ Investigation on 30GPa% Grade Ultrahigh-Strength Martensitic-Austenitic Steels,” Ph.D. thesis, Central Iron and Steel Research Institute, Beijing, China (in Chinese).
Han, Q. , Bi, W. , Jin, X. , Xu, W. , Wang, L. , Xiong, X. , Wang, J. , and Belager, P. , 2015, “ Low Temperature Hot Forming of Medium-Mn Steel,” 5th International Conference on Hot Sheet Metal Forming of High-Performance Steel, Toronto, ON, pp. 381–390.
Jin, J. , and Shi, J. , 2000, “ Diagnostic Feature Extraction From Stamping Tonnage Signals Based on Design of Experiments,” ASME J. Manuf. Sci. Eng., 122(2), pp. 360–369. [CrossRef]
Wang, H. P. , Zhao, K. M. , Hu, P. , Fu, Z. C. , and Bao, J. R. , 2011, “ Investigation and Correction of Surface Distortion in Dies With Typical Depression Features,” ASME J. Manuf. Sci. Eng., 133(4), p. 041004. [CrossRef]
Li, S. H. , He, J. , Xia, Z. C. , Zeng, D. , and Hou, B. , 2014, “ Bifurcation Analysis of Forming Limits for an Orthotropic Sheet Metal,” ASME J. Manuf. Sci. Eng., 136(5), p. 051005. [CrossRef]
Hasan, R. , Kasikci, T. , Tsukrov, I. , and Kinsey, B. , 2014, “ Numerical and Experimental Investigations of Key Assumptions in Analytical Failure Models for Sheet Metal Forming,” ASME J. Manuf. Sci. Eng., 136(1), p. 011013. [CrossRef]
Cui, J. J. , Lei, C. X. , Xing, Z. W. , and Li, C. F. , 2012, “ Microstructure Distribution and Mechanical Properties Prediction of Boron Alloy During Hot Forming Using FE Simulation,” Mater. Sci. Eng. A, 535, pp. 241–251. [CrossRef]
Chang, Y. , Li, X. D. , Zhao, K. M. , Wang, C. Y. , Zheng, G. J. , Hu, P. , and Dong, H. , 2015, “ Influence of Stress on Martensitic Transformation and Mechanical Properties of Hot Stamped AHSS Parts,” Mater. Sci. Eng. A, 629, pp. 1–7. [CrossRef]
Wang, C. Y. , Shi, J. , Cao, W. Q. , and Dong, H. , 2010, “ Characterization of Microstructure Obtained by Quenching and Partitioning Process in Low Alloy Martensitic Steel,” Mater. Sci. Eng. A, 527(15), pp. 3442–3449. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

The CCT curves of the medium-Mn steel sheet

Grahic Jump Location
Fig. 2

(a) Microstructure examined by transmission electron microscopy (TEM) (austenite with stacking fault and/or annealing twin) and (b) microstructure characterized by electron backscatter diffraction (EBSD) (white-colored phase is the retained austenite)

Grahic Jump Location
Fig. 3

Tensile test specimen of the as-received material

Grahic Jump Location
Fig. 4

Tensile test specimen cut from the B-pillar

Grahic Jump Location
Fig. 5

The effect of process parameters on tensile strength (a), elongation (b), and Vickers hardness (c)

Grahic Jump Location
Fig. 6

The warm-stamped B-pillars of medium-Mn steel

Grahic Jump Location
Fig. 7

The micrograph of the B-pillar at selected locations

Grahic Jump Location
Fig. 8

The mechanical properties of medium-Mn steel part at examined locations

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In