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利用相场法模拟了过冷纯金属熔体中的枝晶生长过程 ,研究了各向导性、界面动力学、热扩散和界面能对枝晶生长的影响 .结果表明 ,热噪声可以促发侧向分支的形成 ,但不影响枝晶尖端的稳态行为 ;随着各向异性的增加 ,枝晶尖端生长速度增加 ,尖端半径减小 ;当界面动力学系数减小及在界面动力学系数小于 1的条件下热扩散系数减小时 ,枝晶尖端生长速度随之减小 ,而尖端半径相应增大 ;界面能趋于增大枝晶尺度并保持界面在扰动下的稳定 ,界面能越大 ,形成侧向分支的趋势越小
The phase-field method was used to simulate the dendrite growth process in undercooled pure metal melt, and the influence of the anisotropy, interfacial dynamics, thermal diffusion and interfacial energy on the dendrite growth was investigated. The results show that the thermal noise can be induced But did not affect the steady-state behavior of the dendrite tip. With the increase of anisotropy, the growth rate of dendrite tip increased and the tip radius decreased. When the interface kinetic coefficient decreased and the dynamic coefficient of interface was less than 1, the growth rate of dendrite tip decreases with the decrease of thermal diffusivity, and the tip radius increases correspondingly. The interfacial energy tends to increase the size of dendrite and keep the interface stable under disturbance, the larger the interface energy is, The smaller the trend of lateral branches