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利用晶体生长的最小过冷度判据．对DD2单晶合金激光重熔过程中重熔区组织的生长速度进行了分析．建立了枝晶尖端主长速度与激光荣扫描速度和固液界面前进速度的关系,根据此分析时熔池组织进行了预测,并与实验结果进行了比较,发现激光熔池中枝晶组织的生长方向强烈地受基材晶粒取向和激光束扫描方向的影响,枝晶生长条件下．择优取向对枝晶生长方向的影响要较热流的影响大,理论预测与实验结果相吻合。
The criterion of minimum undercooling using crystal growth. The growth rate of the remelted zone in DD2 single crystal alloy during laser remelting was analyzed. The relationship between the tip speed of the dendrites and the scan speed of the laser and the advancing speed of the solid-liquid interface was established. According to the analysis, the structure of the weld pool was predicted and compared with the experimental results. It was found that the dendritic structure The growth direction is strongly affected by the orientation of the substrate grains and the direction of laser beam scanning, under the dendritic growth conditions. The influence of preferred orientation on the growth direction of dendrites is greater than that of heat flow, and the theoretical prediction is in good agreement with the experimental results.