绿柱石晶体腐蚀像立体模型的建立及{0001}面腐蚀随时间变化的探讨

Three-dimensional Model of Etch Figure on Beryl Crystal and the Evolution of Etching Figure on {0001} Various with Corrosion Time

本文采用物质的量比为1∶1的NaOH-KOH混合熔融物和纯NaOH熔融物对绿柱石晶体各种不同结晶学方向的切面进行腐蚀实验,建立了绿柱石腐蚀像的立体模型,并探讨了绿柱石{0001}切面腐蚀坑随腐蚀时间的变化规律。研究发现绿柱石切面腐蚀像能很好地反映晶体的对称特点,晶体各切面的腐蚀坑形态在三维空间分布的立体模型和投影图可用来进行绿柱石晶体的定向。{0001}切面腐蚀坑随腐蚀时间的延长,会呈现从最初浑圆不太规则状到逐渐稳定呈正六边形的变化,且腐蚀坑有逐渐从小变大、由少变多的特点。该研究对晶体腐蚀机理的探讨及绿柱石腐蚀像应用于晶体定向具有理论和实际意义。

The beryl crystal were corroded using the melt with mole ratio of 1：1 NaOH-KOH mixture and pure NaOH. The etch figures on sections with different crystallographic directions had been observed, and a three-dimensional model of etch figures had been established. The evolution of etching figure on {0001 } various with corrosion time had been observed. It is found that etch figures could reflect the symmetry characteristics of beryl crystal. So the three-dimensional model of etch figures and the stereographic projection diagram could be used for the crystallography orientation of beryl. The etch figure of {0001} evolving during corrosion time were also observed： The shape form irregular to regular, the size and the number increasing gradually. This research is of theoretical and practical significance to the corrosion mechanism and the crystallography orientation of beryl.