M.E Li
,
G.C. Yang
,
null
,
null
金属学报(英文版)
Two new classes of growth morphologies, called doublons and seaweed, were simulated using a phase-field method. The evolution of doublon and seaweed morphologies was obtained in directional solidification. The influence of orientation and velocity on the growth morphology was investigated. It was indicated that doublons preferred growing with its crystallographic axis aligned with the heat flow direction. Seaweed, on the other hand, could be obtained by tilting the crystalline axis to 45°. Stable doublons could only exist in a range of velocity regime. Beyond this regime the patterns formed would be unstable. The simulation results agreed with the reported experimental results qualitatively.
关键词:
growth morphologies
,
null
,
null
姜雪宁
,
孟昕
,
孟宪芹
,
张庆瑜
功能材料
利用反应磁控溅射方法在蓝宝石单晶衬底上制备了调制周期相同、周期数不同的GDC/YSZ纳米多层薄膜,采用X射线衍射、原子力显微镜对薄膜结构、粗糙度、生长形貌进行了表征,利用交流阻抗谱仪测试了多层薄膜不同温度下的电学性能。结果表明衬底上首层薄膜是整个多层膜的生长模板,首先沉积GDC时多层膜呈无规则生长而首先沉积YSZ时多层膜为（111）织构;GDC/YSZ多层膜的生长是一个逐渐粗糙化的过程,随着薄膜厚度的增大（周期数的增多）,多层膜粗糙度与晶粒尺寸增大;随着周期数的增多,多层膜电导率逐渐增大,但电导活化能基本保持不变（约1.3eV）;在500～800℃下退火,多层膜结构稳定,但由于薄膜晶粒长大,导致其电导率小幅降低（降低百分比〈5%）。
关键词:
GDC/YSZ多层薄膜
,
周期数
,
生长形貌
,
电学性能
,
结构稳定性
