Effects of Nb on Strain-Induced Precipitation of NbC and Static Recrystallization for High Nb Pipeline Steels

Abstract:

Strain-induced precipitation of complex carbonitrides and recrystallization for three high-Nb pipeline steels with different Nb and C content have been studied by using a stress relaxation technique and two-passes interrupted compression test. Sequentially, the PTT diagrams were obtained, and static recrystallization activation energy was calculated. Furthermore, the effects of Nb and C content on strain-induced NbC precipitation and static recrystallization were discussed. The results confirm the faster kinetics of precipitation and its retarded recrystallization in the case of higher Nb pipeline steel, and that the recrystallization is easier in low Nb pipeline steel in comparison to the case of high Nb steel. However, the effects of Nb on strain-induced precipitation and static recrystallization were associated with the Nb/C ratio. The precipitation start time (Ps) of strain-induced NbC is delayed in lower Nb/C ratio pipeline steel. It is suggested that the reduced supersaturation of Nb can result in the delay of precipitation of strain-induced NbC carbides forming in the low Nb/C ratio steel.

• Periodical: Advanced Materials Research (Volumes 146-147)
• Pages: 1315-1321
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.146-147.1315
• Online since: October 2010
• Authors: Gui Ying Qiao, Fu Ren Xiao, Xiao Bing Zhang, Shao Hui Chen, Bo Liao
• Keywords: High-Nb Steel, Static Recrystallization, Strain-Induced Precipitation

References

[1] J.Y. Yoo, S.S. Ahm and W.Y. Choo. In: Proc. of Int. Pipeline Technology Conference, Ostend, Belgium, Vol. 3 (2004), pp.1089-1098.

[2] K. Hulka, J.M. Gray and F. Heiterkamp. Niobium Technical Report 16/90, CBMM, Sao Paulo, Brazil, (1990).

[3] Fu-ren Xiao, Bo Liao, Yi-yin Shan, Gui-ying Qiao, Yong Zhong, Chun-ling Zhang and Ke Yang. Mater Sci Eng A, Vol. 431 (2006), pp.41-52.

[4] Y. Wang, K. Yang, Y. Shan, M. Zhao, B. Qian. In: Proceeding of the International Pipe Dreamer's Conference, Yokohama, Japan, (2002), pp.53-59.

[5] C. M. Sellars, The Metals Society, London, (1980), p.2.

[6] D.G. Stalheim and S.G. Jansto. In: Proceedings of the Biennial International Pipeline Conference, IPC, Vol. 3(Part A) (2007), pp.99-106.

[7] D.G. Stalheim. Iron and Steel, Vol. 40(Supplement) (2005), pp.699-704.

[8] K.J. Lee, Scripta Materialia, Vol. 40 (1999), pp.837-843.

[9] S. -H. Cho, K. -B. Kang and J.J. Jonas. ISIJ Inter, Vol. 41 (2001), pp.766-773.

[10] S. -H. Cho, K. -B. Kang and J.J. Jonas. Dynamic, static and metadynamic recrystallization of a Nb-microalloyed steel. ISIJ Inter, Vol 41 (2001), pp.63-69.

DOI: 10.2355/isijinternational.41.63

[11] A. Laasraoui, J.J. Jonas. Metall Trans A, Vol. 22 (1991), pp.151-160.

[12] A. Pandit, A. Murugaiyan, A. Saha Podder, A. Haldar, D. Bhattacharjee, S. Chandra, R.K. Ray. Scripta Materialia, Vol. 53 (2005), pp.1309-1314.

DOI: 10.1016/j.scriptamat.2005.07.003

[13] B. Dutta, C. M. Sellars. Mater Sci Technol, Vol. 3 (1987), pp.197-206.

[14] S.F. Medina and A. Quispe. ISIJ Inter, Vol. 41 (2001), pp.774-781.