Primary spacing selection of CuMn alloy under laser rapid solidification condition

摘要: In order to investigate the primary spacing selection under rapid solidification conditions, laser surface resolidification experiments have been performed on Cu-26.6 wt.% Mn alloy. By taking transverse and then longitudinal sections of directional growth dendrites/cells in traces, average spacing, distribution range as well corresponding rate are quantitatively measured by SEM image analyser. It has found that there exists a wide condition. As increases, both decrease. The maximum, λ1max, minimum, λ1min, \gl1, functions rate, Vs, can be given λ1max = 10.68V− 0.28s, λ1min 2.42V− 0.22s, \gl1 510V− 0.33s, respectively. Our experimental results compared with current KGT model for dendritic growth, good agreement is found.