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Effect of heat input on microstructure and toughness of coarse grain heat affected zone in Nb microalloyed HSLA steels

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Abstract

The influence of Nb on microstructure, mechanical property and the transformation kinetics of the coarse grain heat affected zone (CGHAZ) in HSLA steels for different heat inputs, has been investigated. When welded at higher heat inputs (100–60 kJ/cm), impact toughness values of the steel without Nb are much higher than those of the steel with Nb, and the lowest span is 153 J at 60 kJ/cm. But only a little higher values are observed at lower heat inputs (40–30 kJ/cm), and the highest span is 68 J at 30 kJ/cm. Dilatation studies indicate that continuous cooling transformation starting temperatures (Ts) of CGHAZ for the steel with Nb are approximately 15–30 °C which are lower than those of the steel without Nb at all heat inputs. For higher heat inputs, Nb in solid solution suppresses ferrite transformation and promotes the formation of granular bainite which has detrimental effect on impact toughness. For lower heat inputs higher Charpy impact energy values in the steel with Nb are associated with the formation of low carbon self-tempered martensite.

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References

  1. Li Y, Crowther D N, Green M J W, et al. The Effect of Vanadium and Niobium on the Properties and Microstructure of the Intercritically Reheated Coarse Grained Heat Affected Zone in Low Carbon Microalloyed Steels [J]. ISIJ Int, 2001, 41 (1): 46.

    Article  Google Scholar 

  2. Hattingh R J, Pienaar G. Weld HAZ Embrittlement of Nb Containing C-Mn Steels [J]. Int J Pres Ves Pip, 1998, 75(9): 661.

    Article  Google Scholar 

  3. Shanmugam S, Misra R D K, Mannering T, et al. Impact Toughness and Microstructure Relationship in Niobium and Vanadium Microalloyed Steels Processed With Varied Cooling Rates to Similar Yield Strength [J]. Mater Sci Eng, 2006, 437A(2): 436.

    Article  Google Scholar 

  4. Shome M, Gupta O P, Mohanty O N. Effect of Simulated Thermal Cycles on the Microstructure of the Heat-Affected Zone in HSLA-80 and HSLA-100 [J]. Metall Mater Trans, 2004, 35A: 985.

    Article  Google Scholar 

  5. Hamada M, Fukada Y, Komizo Y. Microstructure and Precipitation Behavior in Heat Affected Zone of C-Mn Microalloyed Steel Containing Nb, V and Ti [J]. ISIJ Int, 1995, 35(10): 1196.

    Article  Google Scholar 

  6. Byun J S, Shim J H, Cho Y W. Influence of Mn on Micro-structural Evolution in Ti-Killed C-Mn Steel [J]. Scripta Mater, 2003, 48(4): 449.

    Article  Google Scholar 

  7. Andrews K W. Empirical Formulae for the Calculation of Some Transformation Temperatures [J]. J Iron Steel Inst, 1965, 203(7): 721.

    Google Scholar 

  8. Bhadeshia H K D H. Diffusional Formation of Ferrite in Iron and Its Alloys [J]. Prog Mater Sci, 1985, 29(4): 321.

    Article  Google Scholar 

  9. Bhadeshia H K D H. Bainite in steels [M]. 2nd eds. London: Institute of Materials, 2001.

    Google Scholar 

  10. Lee S, Kim B C, Kwon D. Correlation of Microstructure and Fracture Properties in Weld Heat-Affected Zones of Thermo-mechanically Controlled Processed Steels [J]. Metall Mater Trans, 1992, 23A(10): 2803.

    Article  Google Scholar 

  11. Irvine K J. Pickering F B, Gladman T. Grain Refined C-Mn Steels [J]. J Iron Steel Inst, 1967, 205(2): 161.

    Google Scholar 

  12. Shome M, Sarma D S, Gupta O P, et al. Precipitate Dissolution and Grain Growth in the Heat Affected Zone of HSLA-100 Steel [J]. ISIJ Int, 2003, 43(9): 1431.

    Article  Google Scholar 

  13. Palmiere E J. Garcia C I. Deardo A J. Compositional and Microstructural Changes Which Attend Reheating and Grain Coarsening in Steels Containing Niobium [J]. Metall Trans, 1994, 25A(2): 277.

    Article  Google Scholar 

  14. Manohar P A, Dunne D P, Chandra T, et al. Grain Growth Predictions in Microalloyed Steels [J]. ISIJ Int, 1996, 36 (2): 194.

    Article  Google Scholar 

  15. Davis C L, King J E. Cleavage Initiation in the Intercriticaily Reheated Coarse-Grained Heat-Affected Zone: Part I. Fractographic Evidence [J]. Metall Mater Trans, 1994, 25A (3): 563.

    Article  Google Scholar 

  16. Bayraktar E, Hugele D, Jansen J P. Evaluation of Pipeline Laser Girth Weld Properties by Charpy (V) Toughness and Impact Tensile Tests [J]. J Mater Pro Tech. 2004, 147(2): 155.

    Article  Google Scholar 

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Authors and Affiliations

  1. Department of Materials Science and Engineering, Shanghai Jiao Tong University, 200030, Shanghai, China

    Ying-qiao Zhang (Doctor), Han-qian Zhang, Jin-fu Li & Wei-ming Liu

  2. Research Institute for Advanced Structural Steel, Research and Development Center, Baoshan Iron and Steel Limited Company, 201900, Shanghai, China

    Han-qian Zhang

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  1. Ying-qiao Zhang
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  2. Han-qian Zhang
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  3. Jin-fu Li
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Correspondence to Ying-qiao Zhang.

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Zhang, Yq., Zhang, Hq., Li, Jf. et al. Effect of heat input on microstructure and toughness of coarse grain heat affected zone in Nb microalloyed HSLA steels. J. Iron Steel Res. Int. 16, 73–80 (2009). https://doi.org/10.1016/S1006-706X(10)60014-3

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  • DOI: https://doi.org/10.1016/S1006-706X(10)60014-3

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