先进材料疑固实验室 Morphology control of crystals Laboratory of Advanced Materials Solidification Negative gradient Interface For substance with rough interface(non- 正∠0 facted morphology):with the increase of x, AT1,t,the crystal grows as dendrites. SjL Undercooling (a)Succinonitrile in free growth (b)Ni dendrites in superalloy spotweld Materials Sollc 上浒充通大学 SHANGHAI JIAO TONG UNIVERSITYMorphology control of crystals Negative gradient For substance with rough interface (non￾facted morphology)：with the increase of x, △Tk , υ  ，the crystal grows as dendrites