A degenerate pattern is seaweed-like morphology with its tip splitting continuously, differing from that the regular dendrite has a stable tip. Here, we carried out bicrystal (BC)-assembled experiments to investigate the competitive growth between a degenerate pattern and regular dendrites in a directionally solidified Al-4.5 wt pct Cu alloy. Using the electron backscattered diffraction (EBSD) technique, we characterized a degenerate pattern that solidified with a (100)45 deg orientation and a dendrite growth comprising (100)0 deg or (100)15 deg orientations. The experimental results for the competitive growth show that the dendrites could overgrow the degenerate pattern completely at V = 15 and 25 µm/s. The grain boundary (GB) in between these two morphologies is not smooth, and its inclination angle θGB is slightly increased with an increase in the growth velocity. For the converging GBs, we find that the dendrites overgrow the degenerate pattern either by generating new primary arm dendrites through tertiary branching or being blocked by the growth of the existing primary arm dendrites, depending on the misorientation arrangement between these two morphologies. The limited growth stability of the degenerate pattern in comparison with the dendrite contributes to deepening the understanding of why the degenerate pattern is not widely prevailing in metallic alloy solidification microstructures.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
1. A. Pineau, G. Guillemot, D. Tourret, A. Karma, and C.A. Gandin: Acta Mater., 2018, vol. 155, pp. 286-301.
2. S.S. Hu, L. Liu, W.C. Yang, J. Zhang, T.W. Huang, Y.C. Wang, and X.D. Zhou: J. Alloy. Compd., 2018, vol. 735, pp. 1878-84.
3. Z.Y. Liu, M. Lin, D. Yu, X.W. Zhou, Y.X. Gu, and H.Z. Fu: Metall. Mater. Trans. A-Phys. Metall. Mater. Sci., 2013, vol. 44A, pp. 5113-21.
4. A.J. Clarke, D. Tourret, Y. Song, S.D. Imhoff, P.J. Gibbs, J.W. Gibbs, K. Fezzaa, and A. Karma: Acta Mater., 2017, vol. 129, pp. 203-16.
Y. Song, S. Akamatsu, S. Bottin-Rousseau, and A. Karma: Phys. Rev. Mater., 2018, vol. 2, p. 053403.
6. D. Walton, and B. Chalmers: Trans. Metall. Soc. AIME, 1959, vol. 215, pp. 447-57.
7. M. Rappaz, and C.A. Gandin: Acta Metall. Mater., 1993, vol. 41, pp. 345-60.
8. S. Akamatsu, G. Faivre, and T. Ihle: Phys. Rev. E, 1995, vol. 51, pp. 4751-73.
9. Y.M. Wang, S.M. Li, Z.P. Liu, H. Zhong, L. Xu, and H. Xing: J. Mater. Sci. Technol., 2019, vol. 35, pp. 1309-14.
B. Utter, and E. Bodenschatz: Phys. Rev. E, 2005, vol. 72, p. 011601.
11. Y. Chen, B. Billia, D.Z. Li, H. Nguyen-Thi, N.M. Xiao, and A.A. Bogno: Acta Mater., 2014, vol. 66, pp. 219-31.
12. N. D’Souza, M.G. Ardakani, A. Wagner, B.A. Shollock, and M. McLean: J. Mater. Sci., 2002, vol. 37, pp. 481-87.
13. Y.Z. Zhou, A. Volek, and N.R. Green: Acta Mater., 2008, vol. 56, pp. 2631-37.
14. H.L. Yu, J.J. Li, X. Lin, L.L. Wang, and W.D. Huang: J. Cryst. Growth, 2014, vol. 402, pp. 210-14.
15. S.S. Hu, W.C. Yang, Q.W. Cui, T.W. Huang, J. Zhang, and L. Liu: Mater. Charact., 2017, vol. 125, pp. 152-59.
16. J. Eiken: Int. J. Cast. Metals Res., 2009, vol. 22, pp. 86-89.
17. J.J. Li, Z.J. Wang, Y.Q. Wang, and J.C. Wang: Acta Mater., 2012, vol. 60, pp. 1478-93.
18. C.W. Guo, J.J. Li, H.L. Yu, Z.J. Wang, X. Lin, and J.C. Wang: Acta Mater., 2017, vol. 136, pp. 148-63.
19. T. Takaki, M. Ohno, Y. Shibuta, S. Sakane, T. Shimokawabe, and T. Aoki: J. Cryst. Growth, 2016, vol. 442, pp. 14-24.
20. T. Takaki, M. Ohno, T. Shimokawabe, and T. Aoki: Acta Mater., 2014, vol. 81, pp. 272-83.
21. D. Tourret, Y. Song, A.J. Clarke, and A. Karma: Acta Mater., 2017, vol. 122, pp. 220-35.
F. Li, L. Jin, Z. Xu, and Z.Q. Guo: Rev. Sci. Instrum., 2009, vol. 80, p. 085106.
23. L.Y. Yang, S.M. Li, Y. Li, K. Fan, and H. Zhong: J. Mater. Res., 2019, vol. 34, pp. 240-50.
H. Xing, X.L. Dong, H.J. Wu, G.H. Hao, J.Y. Wang, C.L. Chen, and K.X. Jin: Sci Rep, 2016, vol. 6, p. 26625.
This research is financially supported by the National Natural Science Foundation of China (No. 51474174), Research Funds of the State Key Laboratory of Solidification Processing in NWPU (No. 2019-TS-01). Yumin Wang thanks Ming Ma from Electronic Materials Research Laboratory of Xian Jiaotong University for his help on RO-XRD tests
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Manuscript submitted April 23, 2019.
About this article
Cite this article
Wang, Y., Li, S., Liu, Z. et al. Competitive Growth of Degenerate Pattern and Dendrites During Directional Solidification of a Bicrystal Metallic Alloy. Metall Mater Trans A 50, 4677–4685 (2019). https://doi.org/10.1007/s11661-019-05401-y