Advertisement

Journal of Materials Engineering and Performance

, Volume 27, Issue 8, pp 4025–4035 | Cite as

Mechanical Properties and Microstructure of High-Strength Steel Controlled by Hot Stamping Process

  • Hang Ou
  • Xu Zhang
  • Junrui Xu
  • Guangyao Li
  • Junjia Cui
Article
  • 101 Downloads

Abstract

A novel design and manufacturing method, dubbed “precast,” of the cooling system and tools for a hot forming process was proposed in this paper. The integrated structures of the punch and blank holder were determined by analyzing the bending and reverse-bending deformation of the forming parts. The desired crashworthiness performance of an automotive front bumper constructed with this process was obtained by a tailored phase transformation, which generated martensite-bainite in the middle and full martensite transformation in the corner areas. Varying cooling effects in the formed parts caused the highest temperature to be located in the bottom and the lowest on the end of the formed parts. Moreover, the microstructural distributions demonstrated that the bottom possessed a relatively lower content of martensite, while, conversely, the end possessed a higher content. This was precisely the most desired phase distributions for the hot formed parts. For the six-process cycle stamping, the temperatures reached a stable status after an initial rapid increase in the first three process cycles. The microstructural results verified the feasibility of the hot forming tools under multiprocess cycles.

Keywords

cooling system hot stamping high-strength steel precast 

Notes

Acknowledgments

This project is supported by the Key Project of Chinese National Programs (No. 2016YFB0101704) and the National Key Research and Development Program of Hunan Province (2017GK2090). We thank Sara Maccagnano-Zacher, Ph.D., from Liwen Bianji, Edanz Editing China (www.liwenbianji.cn/ac), for editing the English text of a draft of this manuscript.

Conflict of interest

The authors declare that they have no conflict of interest.

References

  1. 1.
    J.J. Cui, G.Y. Sun, J.R. Xu, X.D. Huang, and G.Y. Li, A Method to Evaluate the Formability of High-Strength Steel in Hot Stamping, Mater. Des., 2015, 77, p 95–109CrossRefGoogle Scholar
  2. 2.
    H.Z. Li, X. Wu, and G.Y. Li, Prediction of Forming Limit Diagrams for 22MnB5 in Hot Stamping Process, J. Mater. Eng. Perform., 2013, 22, p 2131–2140Google Scholar
  3. 3.
    J.J. Cui, C.X. Lei, Z.W. Xing, C.F. Li, and S.M. Ma, Predictions of the Mechanical Properties and Microstructure Evolution of High Strength Steel in Hot Stamping, J. Mater. Eng. Perform., 2012, 21, p 2241–2254CrossRefGoogle Scholar
  4. 4.
    P. Bosetti, S. Bruschi, T. Stoehr, J. Lechler, and M. Merklein, Interlaboratory Comparison for Heat Transfer Coefficient Identification in Hot Stamping of High Strength Steels, Int. J. Mater. Form., 2010, 3(1), p 817–820CrossRefGoogle Scholar
  5. 5.
    M. Nikravesh, M. Naderi, G.H. Akbari, and W. Bleck, Phase Transformations in a Simulated Hot Stamping Process of the Boron Bearing Steel, Mater. Des., 2015, 84, p 18–24CrossRefGoogle Scholar
  6. 6.
    J. Lechler, M. Merklein, and M. Geiger, Determination of Thermal and Mechanical Material Properties of Ultra-High Strength Steels for Hot Stamping, Steel Res. Int., 2008, 79, p 98–104CrossRefGoogle Scholar
  7. 7.
    B. Abdulhay, B. Bourouga, and C. Dessain, Thermal Contact Resistance Estimation: Influence of the Pressure Contact and the Coating Layer During a Hot Forming Process, Int. J. Mater. Form., 2012, 5, p 1–15CrossRefGoogle Scholar
  8. 8.
    H.S. Liu, Z.W. Xing, J. Bao, and B.Y. Song, Investigation of the Hot-Stamping Process for Advanced High-Strength Steel Sheet by Numerical Simulation, J. Mater. Eng. Perform., 2010, 19, p 325–334CrossRefGoogle Scholar
  9. 9.
    S. Li, L.H. Zhou, X.C. Wu, Y. Zhang, and J.W. Li, The Influence of Thermal Conductivity of Die Material on the Efficiency of Hot-Stamping Process, J. Mater. Eng. Perform., 2016, 25, p 4848–4867CrossRefGoogle Scholar
  10. 10.
    H.S. Liu, C.X. Lei, and Z.W. Xing, Cooling System of Hot Stamping of Quenchable Steel BR1500HS: Optimization and Manufacturing Methods, Int. J. Adv. Manuf. Technol., 2013, 69, p 211–223CrossRefGoogle Scholar
  11. 11.
    M. Abbasi, M. Naderi, and A. Saeed-Akbari, Isothermal versus Non-Isothermal Hot Compression Process: A Comparative Study on Phase Transformations and Structure–Property Relationships, Mater. Des., 2013, 45, p 1–5CrossRefGoogle Scholar
  12. 12.
    Ch. Hopmann and P. Nikoleizig, Inverse Thermal Mold Design for Injection Molds, Int. J. Mater. Form., 2012, 1, p 1–12.  https://doi.org/10.1007/s12289-016-1334-3 Google Scholar
  13. 13.
    H. Steinbeiss, H. So, T. Michelitsch, and H. Hoffmann, Method for Optimizing the Cooling Design of Hot Stamping Tools, Prod. Eng. Res. Devel., 2007, 1, p 149–155CrossRefGoogle Scholar
  14. 14.
    H. Hoffmann, H. So, and H. Steinbeiss, Design of Hot Stamping Tools with Cooling System, CIRP Ann. Manuf. Technol., 2007, 56, p 269–272CrossRefGoogle Scholar
  15. 15.
    K. Mori, T. Maeno, and K. Mongkolkaji, Tailored Die Quenching of Steel Parts Having Strength Distribution Using Bypass Resistance Heating in Hot Stamping, J. Mater. Process. Technol., 2013, 213, p 508–514CrossRefGoogle Scholar
  16. 16.
    M. Merklein, M. Wieland, M. Lechler, S. Bruschi, and A. Ghiotti, Hot Stamping of Boron Steel Sheets with Tailored Properties: A Review, J. Mater. Process. Technol., 2016, 228, p 11–24CrossRefGoogle Scholar
  17. 17.
    T. Stöhr, M. Merklein, and J. Lechler, Investigations on Different Strategies for Influencing the Microstructural Properties with Respect to Partial Hot Stamping. In: 2nd International Conference on Hot Sheet Metal Forming of High-Performance Steel, ed. by M. Merklein, 15–17 June 2009 (Luleå), Verlag Wissenschaftliche Scripten, 2009, p 273–281Google Scholar
  18. 18.
    J. Brecht, B. Goeddeke, and K. Mongkolkaji, Warmgeformte Tailor Rolled Products, Funktionsoptimaler Leichtbau für die Fahrzeugkarosserie, In: Proceedings of the 8th Erlanger Workshop Warmblechumformung, ed. by M. Merklein, 12 Nov 2013 (Erlangen), Lehrstuhl für Fertigungstechnologie, p 85–94 (in German)Google Scholar
  19. 19.
    Y.Q. Zhu and J.L. Wang, Study of a SUV Bumper’s Crashworthiness Based on TRB Structure, Front. Mech. Eng., 2013, 4, p 53–56Google Scholar
  20. 20.
    H. Karbasian A. Brosiu, A. E. Tekkaya, J. Lechler, and M. Merklein, Numerical process design of hot stamping processes based on verified thermo-mechanical characteristics, In: Materials Science and Technology Conference (MS&T), ed. by M. Merklein, 5–9 October 2008 (Pittsburgh), p. 1733–1743.Google Scholar
  21. 21.
    H.S. Park and X.P. Dang, Development of a Smart Plastic injection mold with conformal cooling channels, Procedia. Manuf., 2017, 10, p 48–59CrossRefGoogle Scholar
  22. 22.
    X.P. Li, F.W. Liu, and N.N. Gong, P. Huang and C. YANG, Enhancing the joining strength of injection-molded polymer-metal hybrids by rapid heating and cooling, J. Mater. Process. Technol., 2017, 249, p 386–393CrossRefGoogle Scholar

Copyright information

© ASM International 2018

Authors and Affiliations

  1. 1.State Key Laboratory of Advanced Design and Manufacturing for Vehicle BodyHunan UniversityChangshaChina
  2. 2.Joint Center for Intelligent New Energy VehicleShanghaiChina
  3. 3.College of Automobile and Mechanical EngineeringChangsha University of Science and TechnologyChangshaChina
  4. 4.School of Mechanical EngineeringXiangtan UniversityXiangtanChina

Personalised recommendations