Liu Y.-C.,Institute 53 of Chinas Ordnance Industry Group |
Zhou Y.-P.,Institute 53 of Chinas Ordnance Industry Group |
Wang X.-R.,Institute 53 of Chinas Ordnance Industry Group |
Meng X.-Y.,Institute 53 of Chinas Ordnance Industry Group |
And 2 more authors.
Wuli Xuebao/Acta Physica Sinica | Year: 2013
The AlxGa1-xN epitaxial film is grown on (0001)-oriented sapphire with a 20 nm thick aluminium nitride buffer layer by metal organic chemical vapor deposition. The thickness of AlxGa1-xN layer with high crystal quality is about 2 μm determined by ultraviolet visible light transmittance spectrum analysis. The homogeneity of aluminium in AlxGa1-xN epitaxial film is tested through the energy Eg at the peak intensity in the deep ultraviolet photoluminescence spectrum. The epitaxial wafer with good homogeneity is used to determine aluminium composition by Rutherford backscattering spectroscopy (RBS). Six samples are measured by tow ion beam analysis laboratories, and the experimental data of RBS random spectrum are simulated by the software. The source of measurement uncertainty is analyzed including the sample homogeneity, pileup correction and counting statistics and so on. The research results show that when the alpha particle is used as incident ion, with 2000 keV energy and 165° scattering angle, the measurement uncertainty of RBS for the determination of aluminium composition (x = 0:8) is 2.0% and the coverage factor k = 2. © 2013 Chinese Physical Society.
Peng G.,Institute 53 of Chinas Ordnance Industry Group |
Feng J.-C.,Institute 53 of Chinas Ordnance Industry Group |
Liu Y.-D.,Institute 53 of Chinas Ordnance Industry Group |
Wang D.-Y.,Institute 53 of Chinas Ordnance Industry Group |
And 2 more authors.
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2011
The "bar-tube" type punch-shear experimental technique was modified and optimized according to the punch-shear technique of Hopkinson bar, based on analysis of material performance and application characteristics of fiber reinforced composite laminates. Some technical problems were resolved, such as the vibration of in-put bar, coaxial adjustment between in-put bar and out-put tube, large dispersion of test results, and so on. The confined dimensions of in-put bar, composite sample, and out-bar tube were determined based on the match analysis among them in dynamic punch-shear experiments. The effect of clearance between bar and tube on punch-shear properties was investigated by finite element analysis. It is revealed 0.2 mm~0.3 mm clearance design is appropriate to 2 mm~4 mm laminate sample against Φ14.5mm in-put bar punch-shear test. Experimental data show that loading rates have a remarkable effect on shear properties of glass fiber reinforced composite laminates.