低温环境下PbTiO_(3)钙钛矿晶粒的演化过程

Evolution process of PbTiO_(3)perovskite grains under low temperature environment

利用透射电子显微镜研究了PbTiO_(3)钙钛矿在低温条件下的晶体结构及晶粒演化过程。结果表明:低温条件下,PbTiO_(3)钙钛矿未出现明显的相转变;在电子束辐照条件下,PbTiO_(3)晶体出现细晶化现象,说明电子束对其结构变化存在诱导作用;在室温和低温环境下,PbTiO_(3)晶体均未产生位错缺陷,且低温环境使晶粒细化过程变慢;电子辐照作用使材料的表面能变大,导致晶粒尺寸变小,从而出现细晶化现象。

The crystal structure and grain evolution process of PbTiO_(3)perovskite under low temperature conditions were studied using transmission electron microscopy.The results show that under low temperature conditions,there was no significant phase transition in PbTiO_(3)perovskite.Under electron beam irradiation conditions,PbTiO_(3)crystals exhibited fine-grained phenomena,indicated that the electron beam had an inducing effect on their structural changes.At room temperature and low temperature,PbTiO_(3)crystals did not produce dislocation defects,and the low temperature environment slowed down the grain refinement process.The effect of electron irradiation increased the surface energy of materials,led to a decrease in grain size and resulted in the phenomenon of fine crystallization.