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Development of Thermal Distortion Analysis Method Based on Inherent Strain for TMCP Steels

TMCP 강판의 고유변형도 기반 열변형 해석법 개발

  • Ha, Yun-Sok (Samsung Heavy Industries CO., LTD., Welding Research Part) ;
  • Yang, Jin-Hyuk (Samsung Heavy Industries CO., LTD., Welding Research Part) ;
  • Won, Seok-Hee (Samsung Heavy Industries CO., LTD., Welding Research Part) ;
  • Yi, Myung-Su (Samsung Heavy Industries CO., LTD., Welding Research Part)
  • 하윤석 (삼성중공업 산업기술연구소 용접연구) ;
  • 양진혁 (삼성중공업 산업기술연구소 용접연구) ;
  • 원석희 (삼성중공업 산업기술연구소 용접연구) ;
  • 이명수 (삼성중공업 산업기술연구소 용접연구)
  • Published : 2008.06.30

Abstract

As ships become to be larger than ever, the thicker plate and the higher tensile steel plate are used in naval shipyard. Though special chemical composition is needed for high-tensile steels, recent high-tensile steels are made by the TMCP(Thermo-Mechanical control process) skill. The increase of yield stress and tensile stress of TMCP steels is induced from bainite phase which is transformed from austenite, but that increased yield stress can be vanished by another additional thermal cycle like welding and heating. As thermal deformations are deeply related by yield stress of material, the study for prediction of plate deformation by heating should reflect principle of TMCP steels. This study developed an algorithm which can calculate inherent strain. In this algorithm, not only the mechanical principles of thermal deformations, but also the predicting of the portion of initial bainite is considered when calculating inherent strain. The simulations of plate deformation by these values showed good agreements with experimental results of normalizing steels and TMCP steels in welding and heating. Finally we made an inherent strain database of steels used in Class rule.

Keywords

References

  1. Gonghyun Jung : A shell-element-based Elastic Analysis Predicting Welding-Induced Distortion for Ship Panels, Journal of Ship Research, 51-2 (2007), 128-136
  2. Jang, C. D., Seo, S. I. and Ko, D. E. : A Study on the Prediction of Deformations of Plates Due to Line Heating using a Simplified Thermal Elasto-plastic Analysis, Journal of Ship Production, 13-1 (1997), 22-27
  3. Ha, Y. S. and Jang, C. D. : An Improved Inherent Strain Analysis for Plate Bending by Line Heating Considering Phase Transformation of Steel, International Journal of Offshore and Polar Engineering, 17-2 (2007), 139-144
  4. Yun Sok Ha, Chang Doo Jang, Jong Tae Kim and Hyung Suk Mun : Analysis of Post-Weld Deformation at the Heat-Affected Zone Using External Forces Based on the Inherent Strain, International Journal of Precision Engineering and Manufacturing, 8-4 (2007), 56-62
  5. Sung Il Seo : Calculation of Welding Distortions by Simplified Thermal Elasto-plastic Analysis, Journal of Ship and Ocean Technology, 8-3 (2004), 40 - 49
  6. Yunsok Ha : Development of Thermal Distortion Analysis Method on Large Shell Structure Using Inherent Strain as Boundary Condition, Journal of SNAK, 45-1 (2008), 93-100 (in Korean) https://doi.org/10.3744/SNAK.2008.45.1.93
  7. S. B. Shin, H. G. Kim and K. G. Kim :The Korean Welding and Joining Society, IWJC 2007, 1291
  8. T. G. Keon, W. Y. Song, H. J. Jeo, M. J. Heo : Study of HT50 TMCP Steels on the HOT Formability, KWS Anuual Autumn meeting, (2007), 6-7
  9. SNAK : Literature Survey for the Further Use of TMCP Steel in Shipbuilding Industries, SNAK, 3-4 (2006)
  10. K. B. Jang : A Study on the Analysis of Welding Residual Stress Considering Martensitic Transformation and the Precise Prediction of Welding Deformation in Arc-spot Welded Structure, Pusan Nat'l University. Ph. D. Thesis, (2001), (In Korea)
  11. M. Atkins : Atlas of continuous cooling transformation diagrams for engineering steels, American Society for Metals, 229 (1980)
  12. M. Avrami : Journal of Chemical .Physics, 7 (1939), 1103 https://doi.org/10.1063/1.1750380
  13. Y. K. Lee : Analysis of Heat Transfer and Thermoelastoplastic Deformation Considering Phase Transformation during Cooling of Speed, Seoul Nat'l University. Ph. D. Thesis, (1996), (In Korea)
  14. Marder, AR, and Krauss, G : The Morphology of Martensite in Iron Carbon Alloys, Trans ASM, 60 (1967), 651-660
  15. Lloyd's Register : Rules for the Manufacture, Testing and Certification of Materials, Lloyd's Register of shipping, July, (2007)
  16. T. Gladman : In Metallurgical Developments in Carbon Steels, The Iron and Steel Institute, Special Report 81 (1963), 68-70
  17. ASTM : Estimating the Average Grain Size of Metals, ASTM Designation, 112-63 (1963)