先进材料疑固实验室 Dendrite arm spacing Laboratory of Advanced Materials Solidification Dendrite morphology in usual casting and ingot making processes remains largely unchanged over wide range of cooling rates.It simply becomes finer as heat is extracted at greater rate. PRIMARY PRIMARY ARMS ARMS (a) FIGURE 5-13 Schematic diagram of dendrite structure in Al-4.5%Cu alloy at (a)50 percent solid and (b)90 percent solid.(From Singh et al.) 熟 上浒充通大学 SHANGHAI JIAO TONG UNIVERSITYDendrite arm spacing Dendrite morphology in usual casting and ingot making processes remains largely unchanged over wide range of cooling rates. It simply becomes finer as heat is extracted at greater rate