材料科学
缩进
阴极发光
打滑(空气动力学)
吕德斯乐队
复合材料
位错
成核
蓝宝石
透射电子显微镜
纤锌矿晶体结构
变形(气象学)
结晶学
光学
光电子学
冶金
发光
化学
纳米技术
有机化学
热力学
激光器
锌
物理
作者
Jodie Bradby,Sergei O. Kucheyev,James Williams,Jennifer Wong-Leung,Michael V. Swain,Paul Munroe,Grace Li,Matthew R. Phillips
摘要
The mechanical deformation of wurtzite GaN epilayers grown on sapphire substrates is studied by spherical indentation, cross-sectional transmission electron microscopy (XTEM), and scanning cathodoluminescence (CL) monochromatic imaging. CL imaging of indents which exhibit plastic deformation (based on indentation data) shows an observable “footprint” of deformation-produced defects that result in a strong reduction in the intensity of CL emission. Multiple discontinuities are observed during loading when the maximum load is above the elastic-plastic threshold, and such a behavior can be correlated with multiple slip bands revealed by XTEM. No evidence of pressure-induced phase transformations is found from within the mechanically damaged regions using selected-area diffraction patterns. The main deformation mechanism appears to be the nucleation of slip on the basal planes, with dislocations being nucleated on additional planes on further loading. XTEM reveals no cracking or delamination in any of the samples studied for loads of up to 250 mN.
科研通智能强力驱动
Strongly Powered by AbleSci AI