Abstract
The effects of B content and austenitizing temperature on hardenability and toughness of Cr–Mo alloy steel have been studied. The results show that the hardenability is deteriorated with increasing B content and austenitizing temperature. With increasing temperature, more and more B containing particles were dissolved in austenite and increase the amount of B atoms segregating at grain boundaries. Moreover, the coarsening grains reduce area of grain boundaries and also increase the amount of B atoms at unit grain boundary, excessive B atoms segregating at grain boundaries promotes precipitation of M2B, which accelerates ferrite nucleation and reduces hardenability. The main elements in M2B phase are Fe, Cr, Mo and B. The B atoms segregating at grain boundaries during austenitizing promote precipitation of M2B during tempering which deteriorate toughness significantly.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Zhu KY, Oberbillig C, Musik CD (2011) Loison and T. Lung. Effect of B and B + Nb on the Bainitic transformation in low carbon steels. Mater Sci Eng A 528(12):4222–4231
Watanabe S, Ohtani H, Kunitake T (1983) The influence of dissolution and precipitation behavior of M23(C, B)6 on the hardenability of boron steels. Trans ISIJ 23(2):120–127
Asahi H (2002) Effects of Mo addition and austenitizing temperature on hardenability of low alloy B-added steels. ISIJ Int 42(10):1150–1155
Mun DJ, Shin EJ, Choi YW, Lee JS, Koo YM (2012) Effects of cooling rate, austenitizing temperature and austenite deformation on the transformation behavior of high-strength B steel. Mater Sci Eng A 545:214–224
Hwang B, Suh DW, Kim SJ (2011) Austenitizing temperature and hardenability of low-carbon boron steels. Scr Mater 64(12):1118–1120
Melloy GF, Summon PR, Podgursky PP (1973) Optimizing the boron effect. Metall Trans 4(10):2279–2289
Taylor KA (1992) Grain-boundary segregation and precipitation of boron in 0.2 percent carbon steels. Metall Mater Trans A 23(1):107–119
Kapadia BM (1987) Effect of boron additions on the toughness of heat-treated low-alloy steels. J Heat Treat 5(1):41–53
Thomas G, Chen YL (1981) Structure and mechanical properties of Fe-Cr-Mo-C alloys with and without boron. Metall Mater Trans A 12(6):933–950
Lanier L, Metauer G, Moukassi M (1994) Microprecipitation in boron-containing high-carbon steels. Mikrochim Acta 114(1):353–361
Zheng YX, Wang FM, Li CR, He YT (2017) Dissolution and precipitation behaviors of boron bearing phase and their effects on hardenability and toughness of 25 CrMoNbB steel. Mater Sci Eng A 701:45–55
Acknowledgements
This work is financially supported by National Nature Science Foundation of China under grant No. 51674020 and No. 51571019 and China’s 13th Plan of Five-year National Key Research and Development Program under grant No. 2016YFB0300102-5.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2018 The Minerals, Metals & Materials Society
About this paper
Cite this paper
Zheng, Y., Wang, F., Li, C., Wu, D., Chen, X., Liu, S. (2018). The Effect of Austenitizing Temperature on Hardenability, Precipitation and Mechanical Properties of Boron Bearing Cr–Mo Alloy Steel. In: Hwang, JY., et al. 9th International Symposium on High-Temperature Metallurgical Processing. TMS 2018. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-319-72138-5_40
Download citation
DOI: https://doi.org/10.1007/978-3-319-72138-5_40
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-72137-8
Online ISBN: 978-3-319-72138-5
eBook Packages: Chemistry and Materials ScienceChemistry and Material Science (R0)