The transition of alpha- phase morphology in highly undercooled eutectic alloyYiping Lu1, Gencang Yang1, Feng Liu1, Haipeng Wang2 and Yaohe Zhou1
1 State Key Laboratory of Solidification Processing Northwestern Polytechnical University - Xi'an 710072, PRC
2 Department of Applied Physics, Northwestern Polytechnical University Xi'an 710072, PRC
received 19 October 2005; accepted in final form 20 February 2006
published online 8 March 2006
High undercooling up to 550 (0.39 was achieved in eutectic melt using glass fluxing combined with the cyclic superheating. According to the microstructure evolution with the initial undercooling, surprisingly, a transition from non-faceted to faceted phase occurs for the as-solidified morphology of the alpha- phase at the undercooling of 390. On the basis of the entropy of fusion criterion and the interface kinetics, this interesting morphology transition at high undercooling is analyzed.
61.82.Bg - Metals and alloys.
68.55.Jk - Structure and morphology; thickness; crystalline orientation and texture.
68.35.Ct - Interface structure and roughness.
© EDP Sciences 2006