研究了EDTA与KCl不同掺杂浓度和不同过饱和比下KDP溶液的成核过程,测定了不同条件下KDP过饱和溶液的诱导期;根据经典成核理论计算了成核热、动力学参数,并分析了溶液稳定性随掺杂浓度的变化情况。利用化学腐蚀法对KDP晶体(100)面进行了腐蚀,得到了清晰的位错蚀坑,并使用光学显微镜观察了(100)面位错蚀坑的分布特点。结果表明,当过饱和度为4%、掺杂浓度为0.01 mol%EDTA和1 mol%KCl时,不仅KDP过饱和溶液的稳定性比较高,而且位错蚀坑的分布比较均匀、密度小,适合高质量的KDP晶体生长。
The nucleation process of KDP solution was investigated under different supersaturation ratio and concentration with EDTA and KCl double doped.The induction period of supersaturation solution under different growth conditions was measured.According to the classical nucleation theory,the thermodynamics and kinetic parameters of nucleation were calculated,and the changes of the solution stability with the concentration of codope were analyzed.The(100) plane of KDP was etched by thechemical etching and dislocation etching pits were obtained,and the distribution characterististics of dislocation etching pits were observed by opticalmicroscopy.The results indicated that higher solution stability,more even distribution of dislocation etching pits and lower dislocation density could be achieved under the condition of the supersaturation value of 4% and the concentration of 0.01 mol% EDTA and 1mol% KCl.This is a proper condition for the growth of high quality KDP crystal.