The effect of Zr–Ti combined deoxidisation, compared with the traditional Al deoxidisation, on inclusion and microstructure in X65 pipeline steels was investigated by means of analytical characterisation techniques such as non-aqueous solution electrolysis method, optical and electron microscopy in conjunction with energy dispersive X-ray spectroscopy and hydrogen-induced cracking test. Large inclusions as well as elongated MnS particles were observed in the conventional Al-deoxidised steel. However, the type and size of inclusions were efficiently controlled in the Zr–Ti-deoxidised steel, in which MnS particles were spheroidised and evenly dispersed in the matrix. Hydrogen-induced cracking test results showed that centre segregation was the main factor accountable for hydrogen-induced cracking in X65 pipeline steels. The Zr–Ti-deoxidised X65 pipeline steel revealed better HIC-resistance performance.
VillalbaE. and AtrensA.: ‘Hydrogen embrittlement and rock bolt stress corrosion cracking’, Eng. Fail. Anal., 2009, 16, 164–175. doi: 10.1016/j.engfailanal.2008.01.004
2.
HuangF., LiuJ., DengZ. J., ChengJ. H., LuZ. H. and LiX. G.: ‘Effect of microstructure and inclusions on hydrogen induced cracking susceptibility and hydrogen trapping efficiency of X120 pipeline steel’, Mater. Sci. Eng. A, 2010, 527, 6997–7001. doi: 10.1016/j.msea.2010.07.022
3.
HejaziD., HaqA. J., YazdipourN., DunneD. P., CalkaA., BarbaroF. and PerelomaE. V.: ‘Effect of manganese content and microstructure on the susceptibility of X70 pipeline steel to hydrogen cracking’, Mater. Sci. Eng. A, 2012, 551, 40–49. doi: 10.1016/j.msea.2012.04.076
4.
JinT. Y., LiuZ. Y. and ChengY. F.: ‘Effect of non-metallic inclusions on hydrogen-induced cracking of API5L X100 steel’, Int. J. Hydrogen Energ., 2010, 35, 8014–8021. doi: 10.1016/j.ijhydene.2010.05.089
5.
SernaS., MartínezH., LópezS. Y., González-RodríguezJ. G. and AlbarránJ. L.: ‘Electrochemical technique applied to evaluate the hydrogen permeability in microalloyed steels’, Int. J. Hydrogen Energ., 2005, 30, 1333–1338. doi: 10.1016/j.ijhydene.2005.04.012
6.
Mohtadi-BonabM. A., SzpunarJ. A., BasuR. and EskandariM.: ‘The mechanism of failure by hydrogen induced cracking in an acidic environment for API 5L X70 pipeline steel’, Int. J. Hydrogen Energ., 2015, 40, 1096–1107. doi: 10.1016/j.ijhydene.2014.11.057
7.
Mohtadi-BonabM. A., SzpunarJ. A. and Razavi-TousiS. S.: ‘A comparative study of hydrogen induced cracking behavior in API 5L X60 and X70 pipeline steels’, Eng. Fai. Anal., 2013, 33, 163–175. doi: 10.1016/j.engfailanal.2013.04.028
8.
DuX. S., CaoW. B., WangC. D., LiS. J., ZhaoJ. Y. and SunY. F.: ‘Effect of microstructures and inclusions on hydrogen-induced cracking and blistering of A537 steel’, Mater. Sci. Eng. A, 2015, 642, 181–186. doi: 10.1016/j.msea.2015.06.085
9.
DomizziG., AnteriG. and Ovejero-GarcíaJ.: ‘Influence of sulphur content and inclusion distribution on the hydrogen induced blister cracking in pressure vessel and pipeline steels’, Corros. Sci., 2001, 43, 325–339. doi: 10.1016/S0010-938X(00)00084-6
10.
LiY., WanX. L., LuW. Y., ShirzadiA. A., IsayevO., HressO. and WuK. M.: ‘Effect of Zr–Ti combined deoxidation on the microstructure and mechanical properties of high-strength low-alloy steels’, Mater. Sci. Eng. A, 2016, 659, 179–187. doi:10.1016/j.msea.2016.02.035
11.
GuoA. M., LiS. R., GuoJ., LiP. H., DingQ. F., WuK. M. and HeX. L.: ‘Effect of zirconium addition on the impact toughness of the heat affected zone in a high strength low alloy pipeline steel’, Mater. Charact., 2008, 59, 134–139. doi: 10.1016/j.matchar.2006.11.028
12.
LuW. Y., MengL. D., WangH. H., WangD. Y., YaoY. K. and WuK. M.: ‘The effect of Ti-Zr deoxidation on the mechanical properties of high strength low alloy steels’, Adv. Mater. Res., 2011, 146–147, 1878–1884.
13.
‘Steel: determination of content of nonmetallic inclusions: micrographic method using standard diagrams’, ISO 4967 Third edition, International Organization, 2013.
14.
WanX. L., WangH. H., ChengL. and WuK. M.: ‘The formation mechanisms of interlocked microstructures in low-carbon high-strength steel weld metals’, Mater. Charact., 2012, 67, 41–51. doi: 10.1016/j.matchar.2012.02.007
15.
‘Evaluation of pipeline and pressure vessel steels for resistance to hydrogen-induced cracking’, NACE standard TM0284-2003, Item No. 21215. NACE International, 2003.
16.
Eliassen and SmithL. (eds.): ‘Guidelines on materials requirements for carbon and low alloy steels (3rd Edition): for H2S-containing environments in oil and gas production’; 2009, London, Maney Publishing.
17.
NiM. S.: ‘Analysis on central segregation of strand’, Continuous Casting, 2001, 6, 24–26. (in Chinese)
ZhaoM. C., ShanY. Y., LiY. H. and YangK.: ‘Effect of microstructure on sulfides stress corrosion cracking of pipeline steels’, Acta Metall. Sin., 2001, 37, 1087–1092. (in Chinese)
20.
StevensR.: ‘An introduction to zirconia’, 2nd edn; 1986, Twickenham, Magnesium Elektron Ltd.
21.
J. G. Speight: ‘Lange's handbook of chemistry’, 16th edn, 1.18; 2004, New York, McGraw-Hill Professional Publishing.
22.
NikolopoulosP., OndracekG. and SotiropoulouD.: ‘Wettability and interfacial energies between zirconia ceramic and liquid metals’, Ceram. Int., 1989, 15, 201–206. doi: 10.1016/0272-8842(89)90039-4
23.
ZhangX. F. and QinR. S.: ‘Controlled motion of electrically neutral microparticles by pulsed direct current’, Sci. Rep., 2015, 5, 10162. doi:10.1038/srep10162
24.
ZhouB., LiG. Q., WanX. L., LiY. and WuK. M.: ‘In-situ observation of grain refinement in the simulated heat-affected zone of high-strength low-alloy steel by Zr–Ti combined deoxidation’, Met. Mater. Int., 2016, 22, 267–275. doi: 10.1007/s12540-016-5301-9
25.
LiY., WanX. L., ChengL. and WuK. M.: ‘First-principles calculation on the interaction of Mn with ZrO2 and its effect on the formation of ferrite in high-strength low-alloy steels’, Scripta Mater., 2014, 75, 78–81. doi: 10.1016/j.scriptamat.2013.11.028
26.
ZhaoM. C., ShanY. Y., XiaoF. R., YangK. and LiY. H.: ‘Investigation on the H2S-resistant behaviors of acicular ferrite and ultrafine ferrite’, Mater. Lett., 2002, 57, 141–145. doi: 10.1016/S0167-577X(02)00720-6
