Cusp instability in cellular growth
نویسندگان
چکیده
During directional solidification of alloys, a cellular structure can be observed above a critical pulling speed. Under certain conditions, the cusps behind the cells can present a secondary instability characterized by a periodic emission of liquid droplets. These droplets are transported by the solid, but also migrate towards the solid-liquid interface by temperature gradient zone migration. We study the conditions of appearance of the droplet instability and discuss the information concerning growth mechanisms that can be deduced from a study of the migration. J. Phys. France 50 (1989) 3007-3019 1er OCTOBRE 1989, Classification Physics Abstracts 61.50C 81.10F 81.30F
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