Cell tip undercooling in directional solidification

• Published in: Journal of crystal growth Vol. 206; no. 3; pp. 215 - 229
• Main Authors: Pocheau, A., Georgelin, M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.10.1999; Elsevier
• Subjects: Cells; Cross-disciplinary physics: materials science; rheology; Dendrites; Directional solidification; Exact sciences and technology; Growth from melts; zone melting and refining; Materials science; Methods of crystal growth; physics of crystal growth; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Physics; Solidification; Tip-temperature; Transparent alloy; Undercooling; Tip-temperature; Directional solidification; Transparent alloy; Undercooling; Dendrites; 47.20.Hw; Cells; 81.10.−h; 81.30.Fb; Liquid solid interface; Growth interface; Binary systems; Succinonitrile; Experimental study; Temperature measurement; Nitriles; Supercooling; Microstructure; Cellular structure; Organic compounds; Crystal growth from melts
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/S0022-0248(99)00335-8

Undercooling Δ t of cell tips in directional solidification of impure succinonitrile is measured with respect to pulling velocity V, thermal gradient and cell spacing. Denoting V c as the critical velocity of planar front destabilization and ν as the reduced velocity V/ V c, the relation νΔ t=1 is evidenced in the cell to near dendritic regime 1⩽ ν⩽17 with a high accuracy. Some of its consequences are drawn.