Combined effect of M/A constituent and grain boundary on the impact toughness of CGHAZ and ICCGHAZ of E550 grade offshore engineering steel

Xuelin Wang; Zhiquan Wang; Zhenjia Xie; Xiaoping Ma; Sundaresa Subramanian; Chengjia Shang; Xiucheng Li; Jingliang Wang; Xuelin Wang; Zhiquan Wang; Zhenjia Xie; Xiaoping Ma; Sundaresa Subramanian; Chengjia Shang; Xiucheng Li; Jingliang Wang

doi:10.3934/mbe.2019376

Mathematical Biosciences and Engineering

2019, Volume 16, Issue 6: 7494-7509. doi: 10.3934/mbe.2019376

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Combined effect of M/A constituent and grain boundary on the impact toughness of CGHAZ and ICCGHAZ of E550 grade offshore engineering steel

1.
Collaborative Innovation Center of Steel Technology, University of Science and Technology Beijing, Beijing 100083, China
2.
Management Committee of High-tech Industrial Development Zone of Tongliang, Chongqing 402560, China
3.
Algoma Steel Inc., Sault Ste. Marie P6A 7B4, Canada
4.
Department of Materials Science and Engineering, McMaster University, Hamilton L8S 4L7, Canada
5.
State Key Laboratory of Metal Materials for Marine Equipment and Applications, Anshan, Liaoning 114021, China

Received: 08 March 2019 Accepted: 31 July 2019 Published: 19 August 2019

The present paper investigated the relationship between low temperature impact toughness and microstructure of bainite in coarse-grained heat affected zone (CGHAZ) and intercritically rehazed CGHAZ (ICCGHAZ) of an offshore engineering steel from both the microstructure morphological and crystallographic aspects. In this work, six groups of samples simulated CGHAZ and ICCGHAZ were designated at three different cooling rates. The Charpy test results showed that the toughness in CGHAZ decreases dramatically with decrease of cooling rate, which was attributed to the microstructural evolution from lath bainite to granular bainite, accompanying with the size increase of Bain zone and the change of M/A morphology from film to block. The increase in hardenability by cooling rate promotes more crystallographic variants from different Bain groups. Meanwhile, the combination with controlled inter-spacing of block boundaries by self-accommodation below the critical Griffith crack length, micro-crack can be arrested by these high angle grain boundaries thereby suppressed brittle fracture initiation and increased fracture properties. However, the variation in toughness of ICCGHAZ is not a concern, since obtaining excellent toughness is scarcely accessible even if the matrix microstructure is analogous to CGHAZ. It was due to the formation of coarse M/A constituents (~2 μm) necklacing at the prior austenite grain boundary. The visualized crystallography suggested that the impact toughness was partially correlated to the configuration manner and the size of Bain zones as well via promoting highly misoriented angle (>45°) boundaries, which in turn effectively deflected or arrested the brittle crack propagation.
- M/A constituent,
- crystallography,
- Bain zone,
- crack propagation,
- impact toughness
Citation: Xuelin Wang, Zhiquan Wang, Zhenjia Xie, Xiaoping Ma, Sundaresa Subramanian, Chengjia Shang, Xiucheng Li, Jingliang Wang. Combined effect of M/A constituent and grain boundary on the impact toughness of CGHAZ and ICCGHAZ of E550 grade offshore engineering steel[J]. Mathematical Biosciences and Engineering, 2019, 16(6): 7494-7509. doi: 10.3934/mbe.2019376

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Abstract

The present paper investigated the relationship between low temperature impact toughness and microstructure of bainite in coarse-grained heat affected zone (CGHAZ) and intercritically rehazed CGHAZ (ICCGHAZ) of an offshore engineering steel from both the microstructure morphological and crystallographic aspects. In this work, six groups of samples simulated CGHAZ and ICCGHAZ were designated at three different cooling rates. The Charpy test results showed that the toughness in CGHAZ decreases dramatically with decrease of cooling rate, which was attributed to the microstructural evolution from lath bainite to granular bainite, accompanying with the size increase of Bain zone and the change of M/A morphology from film to block. The increase in hardenability by cooling rate promotes more crystallographic variants from different Bain groups. Meanwhile, the combination with controlled inter-spacing of block boundaries by self-accommodation below the critical Griffith crack length, micro-crack can be arrested by these high angle grain boundaries thereby suppressed brittle fracture initiation and increased fracture properties. However, the variation in toughness of ICCGHAZ is not a concern, since obtaining excellent toughness is scarcely accessible even if the matrix microstructure is analogous to CGHAZ. It was due to the formation of coarse M/A constituents (~2 μm) necklacing at the prior austenite grain boundary. The visualized crystallography suggested that the impact toughness was partially correlated to the configuration manner and the size of Bain zones as well via promoting highly misoriented angle (>45°) boundaries, which in turn effectively deflected or arrested the brittle crack propagation.

References

[1]	D. S. Liu, Q. L. Li and T. Emi, Microstructure and mechanical properties in hot-rolled extra high-yield-strength steel plates for offshore structure and shipbuilding, Metall. Mater. Trans. A, 42 (2011), 1349–1361.
[2]	Y. L. Zhou, T. Jia, X. J. Zhang, et al., Microstructure and toughness of the CGHAZ of an offshore platform steel, J. Mater. Process. Tech., 219 (2015), 314–320.
[3]	Y. You, C. J. Shang, L. Chen, et al., Investigation on the crystallography of the transformation products of reverted austenite in intercritically reheated coarse grained heat affected zone, Mater. Des., 43 (2013), 485–491.
[4]	X. D. Li, X. P. Ma, S. V. Subramanian, et al., Structure-property-fracture mechanism correlation in heat-affected zone of X100 ferrite-bainite pipeline steel, Metall. Mater. Trans. E, 2 (2015), 1–11.
[5]	C. L. Davis and J. E. King, Cleavage initiation in the intercritically reheated coarse grained heat affected zone, Metall. Mater. Trans. A, 25 (1994), 563–573.
[6]	A. Lambert-Perlade, A. F. Gourgues, J. Besson, et al., Mechanisms and modeling of cleavage fracture in simulated heat-affected zone microstructures of a high-strength low alloy steel, Metall. Mater. Trans. A, 35 (2004), 1039–1053.
[7]	Y. Li and T. N. Baker, Effct of morphology of martensite-austenite phase on fracture of weld heat affected zone in vanadium and niobium microalloyed steels, Mater. Sci. Technol., 26 (2010), 1029–1040.
[8]	L. Y. Lan, C. L. Qiu, D. W. Zhao, et al., Microstructural characteristics and toughness of the simulated coarse grained heat affcted zone of high strength low carbon bainitic steel, Mater. Sci. Eng. A, 529 (2011), 192–200.
[9]	Y. You, C. J. Shang, W. J. Nie, et al., Investigation on the microstructure and toughness of coarse grained heat affected zone in X-100 multi-phase pipeline steel with high Nb content, Mater. Sci. Eng. A, 558 (2012), 692–701.
[10]	Z. X. Zhu, J. Han and H. J. Li, Influence of heat input on microstructure and toughness properties in simulated CGHAZ of X80 steel manufactured using high-temperature processing, Metall. Mater. Trans. A, 46 (2015), 5467–5475.
[11]	J. Hu, L. X. Du, J. J. Wang, et al., Effect of welding heat input on microstructures and toughness in simulated CGHAZ of V-N high strength steel, Mater. Sci. Eng. A, 577 (2013), 161–168.
[12]	X. D. Li, Y. R. Fan, X. P. Ma, et al., Influence of martensite-austenite constituents formed at different intercritical temperatures on toughness, Mater. Des., 67 (2015), 457–463.
[13]	X. D. Li, X. P. Ma, S. V. Subramanian, et al., EBSD characterization of secondary microcracks in the heat affected zone of a X100 pipeline steel weld joint, Int. J. Fract., 193 (2015), 131–139.
[14]	X. D. Li, C. J. Shang, X. P. Ma, et al., Elemental distribution in the martensite-austenite constituent in intercritically reheated coarse-grained heat-affected zone of a high-strength pipeline steel, Script. Mater., 139 (2017), 67–70.
[15]	X. D. Li, C. J. Shang, X. P. Ma, et al., Structure and crystallography of martensite-austenite constituent in the intercritically reheated coarse-grained heat affected zone of a high strength pipeline steel, Mater. Charact. 138 (2018), 107–112.
[16]	C. Cayron, ARPGE: a computer program to automatically reconstruct the parent grains from electron backscatter diffraction data, J. Appl. Cryst., 40 (2007), 1183–1188.
[17]	Y. Zhong, F. R. Xiao, J. W. Zhang, et al., In situ TEM study of the effect of M/A films at grain boundaries on crack propagation in an ultra-fine acicular ferrite pipeline steel, Acta Mater., 54 (2006), 435–443.
[18]	X. D. Li, X. P. Ma, S. V. Subramanian, et al., Influence of prior austenite grain size on martensite-austenite constituent and toughness in the heat affected zone of 700 MPa high strength linepipe steel, Mater. Sci. Eng. A, 616 (2014), 141–147.
[19]	X. L. Wang, Z. Q. Wang, X. P. Ma, et al., Analysis of impact toughness scatter in simulated coarse-grained HAZ of E550 grade offshore engineering steel from the aspect of crystallographic structure, Mater. Charact., 140 (2018), 312–319.
[20]	H. Terasaki, Y. Shintome, Y. I. Komizo, et al., Effect of close-packed plane boundaries in a Bain zone on the crack path in simulated coarse-grained HAZ of bainitic Steel, Metall. Mater. Trans. A, 46 (2015), 2035–2039.
[21]	H. Terasaki, Y. Miyahara, M. Ohata, et al., Visualization of microstructural factor resisting the cleavage-crack propagation in the simulated heat affected zone of bainitic Steel, Metall. Mater. Trans. A, 46 (2015), 5489–5493.
[22]	M. Tsuboi, A. Shibata, D. Terada, et al., Role of different kinds of boundaries against cleavage crack propagation in low-temperature embrittlement of low-carbon martensitic steel, Metall. Mater. Trans. A, 48 (2017), 3261–3268.
[23]	X. L. Wang, Z. Q. Wang, L. L. Dong, et al., New insights into the mechanism of cooling rate on the impact toughness of coarse grained heat affected zone from the aspect of variant selection, Mater. Sci. Eng. A, 704 (2017), 448–458.
[24]	Y. You, C. J. Shang and S. Subramanian, Effect of Ni addition on toughness and microstructure evolution in coarse grain heat affected zone, Met. Mater. Int., 20 (2014), 659–668.
[25]	F. Matsuda, K. Ikeuchi, Y. Fukada, et al., Review of Mechanical and Metallurgical Investigations of M-A Constituent in Welded Joint in Japan, Trans. JWRI., 24 (1995), 1–24.
[26]	R. Danilo and G. Vladimir, Simulations of transformation kinetics in a multi-pass weld, Mater. Manuf. Process., 20 (2005), 833–849.
[27]	A. Ghosh, S. Kundu and D. Chakrabarti, Effect of crystallographic texture on the cleavage fracture mechanism and effective grain size of ferritic steel, Scr. Mater., 81 (2014), 8–11.
[28]	S. V. Subramanian, X. P. Ma and L. Collins, Structure-property studies on HAZ toughness of niobium microalloyed linepipe steels, 6th International Pipeline Technology Conference, Ostend, October, (2013), 1–25.
[29]	X. L. Wang, Y. R. Nan, Z. J. Xie, et al., Influence of welding pass on microstructure and toughness in the reheated zone of multi-pass weld metal of 550 MPa offshore engineering steel, Mater. Sci. Eng. A, 702 (2017), 196–205.
[30]	X. L. Wang, X. M. Wang, C. J. Shang, et al., Characterization of the multi-pass weld metal and the impact of retained austenite obtained through intercritical heat treatment on low temperature toughness, Mater. Sci. Eng. A, 649 (2016), 282–292.
[31]	X. P. Ma, X. D. Li, B. Langelier, et al., Effects of carbon variation on microstructure evolution in weld heat-affected zone of Nb-Ti microalloyed steels, Metall. Mater. Trans. A, 49 (2018), 4824-4837.
[32]	A. D. Schino and P. E. D. Nunzio, Effect of Nb microalloying on the heat affected zone microstructure of girth welded joints, Mater. Lett., 186 (2017), 86–89.
[33]	C. Fossaert, G. Rees, T. Maurickx, et al., The effect of niobium on the hardenability of microalloyed austenite, Metall. Mater. Trans. A, 26 (1995), 21–30.
[34]	G. I. Rees, J. Perdrix, T. Maurickx, et al., The effect of niobium in solid solution on the transformation kinetics of bainite, Mater. Sci. Eng. A, 194 (1995), 179–186.

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