【摘要】 在70～95GPa的高压下,对低密相六方氮化硼进行冲击处理;实验结果发现,普通低密相六方氮化硼在单次冲击下部分转化为纤锌矿型和立方型氮化硼的混合物.根据晶体结构之间的对应性,文中对相变过程进行了探讨,认为六方氮化硼向纤锌矿型的转化其晶体结构无须发生切变;而向立方型氮化硼的转变其晶体的切变是必不可少的,这种相变主要依靠高压下位错运动而产生.更多还原

【Abstract】 At the range of 70-95GPa pressure, graphite-like boron nitride was shock-compressed, the experimentalresults showed that the graphite-like boron nitride were transformed into the mixture of wurtzite-type and zinc blende-type boron nitrides (wBN & CBN). According to the relations of crystal structure,the mechanism of shock-induced phase transformation was analyzed in the paper. During the phase transformation from hexagonal boron nitride (hBN) to wurtzite-type,hBN crystal do not have to be sheared,but it is necessary to shear hBN crystal during the transformation to CBN. Therefore, the phase transformation to CBN must be related to the dislocation motion in crystal under high pressure.更多还原