DOI QR코드

DOI QR Code

Optimization of Resistance Spot Weld Condition for Single Lap Joint of Hot Stamped 22MnB5 by Taking Heating Temperature and Heating Time into Consideration

핫스템핑 공정에서 가열온도 및 유지시간을 고려한 22MnB5의 단일겹치기 저항 점용접 조건 최적화

  • Choi, Hong-Seok (Division of Precision and Manufacturing Systems, Pusan Nat'l Univ.) ;
  • Kim, Byung-Min (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Park, Geun-Hwan (Division of Precision and Manufacturing Systems, Pusan Nat'l Univ.) ;
  • Lim, Woo-Seung (Division of Precision and Manufacturing Systems, Pusan Nat'l Univ.) ;
  • Lee, Sun-Bong (School of Mechanical and Automotive Engineering, Keimyung Univ.)
  • 최홍석 (부산대학교 정밀가공시스템) ;
  • 김병민 (부산대학교 기계공학부) ;
  • 박근환 (부산대학교 정밀가공시스템) ;
  • 임우승 (부산대학교 정밀가공시스템) ;
  • 이선봉 (계명대학교 기계자동차공학부)
  • Received : 2010.03.12
  • Accepted : 2010.07.23
  • Published : 2010.10.01

Abstract

In this study, optimization of the process parameters of the resistance spot welding of a sheet of aluminum-coated boron alloyed steel, 22MnB5, used in hot stamping has been performed by a Taguchi method to increase the strength of the weld joint. The process parameters selected were current, electrode force, and weld time. The heating temperature and heating time of 22MnB5 are considered to be noise factors. It was known that the variation in the thickness of the intermetallic compound layer between the aluminum-coated layer and the substrate, which influences on the formation of nugget, was generated due to the difference of diffusion reaction according to heating conditions. From the results of spot weld experiment, the optimum weld condition was determined to be when the current, electrode force, and weld time were 8kA, 4kN, and 18 cycles, respectively. The result of a test performed to verify the optimized weld condition showed that the tensile strength of the weld joint was over 32kN, which is considerably higher than the required strength, i.e., 23kN.

Keywords

Hot Stamping;22MnB5;Resistance Spot Welding;Single Lap Shear Test;Taguchi Method;Intermetallic Compound Layer

Acknowledgement

Supported by : 한국연구재단

References

  1. POSCO Co. LTD, 2008, Automotive Steel Data Book, Copylight by POSCO, pp. 47-68.
  2. Lim, H. T., Suh, C. H., Youn, H. C., Ro, H. C., Shin, H. D., Kwak, Y. S. and Park, C. D., 2009, "A Study on the Forming Process of Automobile Center Floor Side Member Using Ultra High Strength Steel of 980MPa," Proc. of the KSTP, pp. 203-206.
  3. Cha, S. H., Lee, S. K., Ko, D. C. and Kim, B. M., 2009, "A Study on the Forming of Automotive Front Side Member Part with Ultra High Strength Steel of DP980," J. of KSTP, Vol. 18, No. 1, pp. 39-44. https://doi.org/10.5228/KSPP.2009.18.1.039
  4. Neugebauer, R., Altan, T., Geiger, M., Kleiner, M. and Sterzing, A., 2006, "Sheet Metal Forming at Elevated Temperatures," Annals of the CIRP, Vol. 55, No. 2, pp. 793-816. https://doi.org/10.1016/j.cirp.2006.10.008
  5. Merklein, M. and Lechler, J., 2006, "Investigation of the Thermo-Mechanical Properties of Hot Stamping Steels," J. of Materials Processing Technology, Vol. 177, pp. 452-455. https://doi.org/10.1016/j.jmatprotec.2006.03.233
  6. Turetta, A., Bruschi, S. and Ghiotti, A., 2006, "Investigation of 22MnB5 Formability in Hot Stamping Operation," J. of Materials Processing Technology, Vol. 177, pp. 396-400. https://doi.org/10.1016/j.jmatprotec.2006.04.041
  7. Hardell, J. and Prakash, B., 2008, "High-temperature Friction and Wear Behavior of Different Tool Steels During Sliding Against Al-Si-coated High-strength Steel," Tribology International, Vol. 41, pp. 663-671. https://doi.org/10.1016/j.triboint.2007.07.013
  8. Saeglits, M., Krauss, G. and Berger, D., 2009, "The Effect of Tempering on Martensitic Micro-structure and Mechanical Properties of 22MnB5 Steel Used for Hot Stamping," Proceedings of IDDRG 2009, pp.637-648.
  9. Berglund, D., 2009, "Hot Stamped Components with Tailored Properties-Simulation and Validation of Product Performance," Proceedings of 2nd Int’l Conference Hot Sheet Metal Forming of High Performance Steel, pp. 293-301.
  10. Braun, M. and Fritzsche., 2009, "Joining of Hot-formed Steel," Proceedings of 2nd Int’l Conference Hot Sheet Metal Forming of High Performance Steel, pp. 313-322.
  11. Totten, G. E., 2006, Steel Heat Treatment-Metallurgy and Technology, Taylor and Francis, New York, pp. 193-196.
  12. KS B 0801, 2007, Test Pieces for Tensile Test for Metallic Materials.
  13. KS D 0850, 2006, Method of Inspection for Spot Weld.
  14. Mori, K. and Ito, D, 2009, "Prevention of Oxidation in Hot Stamping of Quenchable Steel Sheet by Oxidation Prevent Oil," CIRP Annals - Manufacturing Technology, Vol. 58, pp. 267-270. https://doi.org/10.1016/j.cirp.2009.03.055
  15. Huang. B., Ishihara. K. N. and Shingu. P. H., 1997, "Metastable Phases of Al-Fe System by Mechanical Alloying," Materials Science and Engineering, A231, pp. 72-79.

Cited by

  1. Evaluation of Mechanical Characteristic of Laser-Welded Blank of a Boron Steel by Using Laser Ablation of Al-Si Coating Layer vol.20, pp.8, 2011, https://doi.org/10.5228/KSTP.2011.20.8.540
  2. A study on mechanical properties of laser-welded blank of a boron sheet steel by laser ablation variable of Al-Si coating layer vol.14, pp.2, 2013, https://doi.org/10.1007/s12541-013-0039-5
  3. A Study on Laser Weldability of Al-Si Coated 22MnB5 Steel for TWB Hot Stamping vol.31, pp.2, 2013, https://doi.org/10.5781/KWJS.2013.31.2.30
  4. Investigation of formability and surface micro-crack in hot deep drawing by using laser-welded blank of Al–Si and Zn-coated boron steel vol.228, pp.4, 2014, https://doi.org/10.1177/0954405413501810
  5. The Study on Weldability of Boron Steel and Hot-Stamped Steel by Using Laser Heat Source (II) - Laser Weldability of Hot Stamping Steel with Ultra-High Strength - vol.38, pp.12, 2014, https://doi.org/10.3795/KSME-A.2014.38.12.1373
  6. Effect of the Die Temperature and Blank Thickness on the Formability of a Laser-Welded Blank of a Boron Steel Sheet with Removing Al-Si Coating Layer vol.6, pp.1687-8140, 2014, https://doi.org/10.1155/2014/925493
  7. Investigation of the Failure of Advanced High Strength Steels Heterogeneous Spot Welds vol.6, pp.5, 2016, https://doi.org/10.3390/met6050111
  8. Effects of Welding Heat Input on 22MnB5 Steel with Hot-Dipping Al Coating vol.690-693, pp.1662-8985, 2013, https://doi.org/10.4028/www.scientific.net/AMR.690-693.2574
  9. The Study on Weldability of Boron Steel and Hot-Stamped Steel by Using Laser Heat Source (I) - Laser Weldability of Al-Si Coated Boron Steel Used for Hot Stamping Process - vol.38, pp.12, 2014, https://doi.org/10.3795/KSME-A.2014.38.12.1367
  10. The Study on Weldability of Boron Steel and Hot-Stamped Steel by Using Laser Heat Source (III) - Comparison on Laser Weldability of Boron Steel and Hot-Stamped Steel - vol.39, pp.1, 2015, https://doi.org/10.3795/KSME-A.2015.39.1.089