Real-time study of thin and bulk eutectic growth in succinonitrile–( d)camphor alloys

• Published in: Journal of crystal growth Vol. 299; no. 2; pp. 418 - 428
• Main Authors: Akamatsu, S., Bottin-Rousseau, S., Perrut, M., Faivre, G., Witusiewicz, V.T., Sturz, L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.02.2007; Elsevier
• Subjects: A1. Directional solidification; A1. Eutectics; Condensed Matter; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Growth from melts; zone melting and refining; Materials science; Methods of crystal growth; physics of crystal growth; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Theory and models of film growth; A1. Eutectics; A1. Directional solidification; 81.30.Fb; Hexagonal lattices; Directional solidification; Eutectics; Growth mechanism; Long-range order; Al. Directional solidification; Al. Eutectics; Succinonitrile; Experimental study; Real time; Crystal growth from melts; Transients; eutectics; directional solidification
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2006.11.271

We study the directional-growth patterns of the transparent nonfaceted alloy succinonitrile–( d)camphor (SCN–DC) at eutectic concentration in thin and bulk samples using real-time observation methods. We measure in situ the minimum-undercooling spacing λ m and the small-spacing stability limit λ c of the thin, quasi-lamellar patterns. We find λ m 2 V ≈ 10.2 μ m 3 s - 1 and λ c ≈ 0.65 λ m . This last result is contrary to the common conjecture that λ c = λ m in lamellar patterns, but in agreement with previous experimental and numerical studies in the CBr 4–C 2Cl 6 eutectic. In bulk samples, we observe the growth of rod-like patterns in real time. We show that these patterns do not usually achieve long-range hexagonal order after long solidification times, although their average spacing reaches a constant value, which is close to λ m , after a relatively short transient.