کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1517777 | 1511590 | 2009 | 6 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Shape-dependent local internal stress of α-Cr2O3 nanocrystal fabricated by pulsed laser ablation Shape-dependent local internal stress of α-Cr2O3 nanocrystal fabricated by pulsed laser ablation](/preview/png/1517777.png)
The α-Cr2O3 single-crystal nanocondensates were fabricated by pulsed laser ablation in air and characterized by analytical electron microscopy regarding shape-dependent local internal stress of the anisotropic crystal. The nanocondensates formed predominantly as rhombohedra with well-developed {011¯2} surfaces and occasionally hexagonal plate with thin {112¯0} edges and blunt corners. Such nanocondensates showed Raman shift for the CrO6 polyhedra, indicating a local compressive stress up to ca. 4 GPa on the average. Careful analysis of the lattice fringes revealed a local compressive stress (0.5% strain) at the thin edge of the hexagonal plates and a local tensile stress (0.3–1.0% strain) near the relaxed {1¯012}, {101¯1}, and (0 0 0 1) surfaces of truncated rhombohedra. The combined effects of nanosize, capillarity force at sharp edge, and specific surface relaxation account for the retention of a local internal compressive stress built up in an anisotropic crystal during a very rapid heating–cooling process.
Journal: Journal of Physics and Chemistry of Solids - Volume 70, Issue 12, December 2009, Pages 1505–1510