ADP点状籽晶(100)面的生长

Growth of ADP point-seed crystal (100) surface

ADP晶体点状籽晶生长实验结果表明:生长温度处于20~40℃,相变驱动力介于0.005KT/ωs^0.03KT/ωs之间时,籽晶(100)晶面的生长速率随过饱和度的增加而线性增加;在相变驱动力一定时,晶面生长速率随温度的升高而呈指数增加;晶面的生长动力学规律与体扩散输运机制下的螺位错生长机制相符;相变驱动力低于临界驱动力时,晶体生长存在着热力学因素造成的死区。相变驱动力介于相变驱动力介于0.05KT/ωs^0.11KT/ωs之间时,(100)晶面的生长速率随过饱和度的增加而呈非线性增加,晶面生长趋近于多二维核生长,但同时也有其它生长机制并存。

growth experiments of ammonium dihydrogen phosphate （ADP） point-seed crystal were employed. And it is shown that the growth rate of （100） surface increases linearly with the increase of super-saturation under the conditions of 0. 005 kT/ωs-0. 03 kT/ωs for phase transition drive force and 20~40 ℃ for the growth temperature. The growth rate of （100） surface increases exponentially with the rise of temperature when drive force is constant. The kinetics mechanism of crystal surface growth is in agreement with the screw dislocation growth under the condition of bulk diffusion transfer mechanism. There is death zone resulting from thermodynamic factors in crystal growth when the drive force is less than the critical value. The growth rate of （100） surface increases nonlinearly with increasing super- saturation when drive force is within 0.05 kT/ωs-0. 11 kT/ωs. The crystal growth is dominated by the 2D- nucleation mechanism with the existence of other growth mechanisms.