Fabrication of micro gratings using a femtosecond laser exposure system is experimentally investigated for the electron moire method. Micro holes and lines are firstly etched for parameter study. Grating profile is th...Fabrication of micro gratings using a femtosecond laser exposure system is experimentally investigated for the electron moire method. Micro holes and lines are firstly etched for parameter study. Grating profile is theoretically optimized to form high quality moire patterns. For a demonstration, a parallel grating is fabricated on a specimen of quartz glass. The minimum line width and the distance between two adjacent lines are both set to be 1 μm, and the frequency of grating is 500 lines/ram. The experimental results indicate that the quality of gratings is good and the relative error of the gratings pitch is about 1.5%. Based on molte method, scanning electron microscope （SEM） moire patterns are observed clearly, which manifests that gratings fabricated with the femtosecond laser exposure is suitable for micro scale deformation measurement.展开更多
The aluminium sheet rolling is studied by using three dimensional elastic-plastic finite element method (FEM) based on considering both material and geometric non linearity.Three dimensional distribution of the stress...The aluminium sheet rolling is studied by using three dimensional elastic-plastic finite element method (FEM) based on considering both material and geometric non linearity.Three dimensional distribution of the stress and deformation are given on the VAX11 / 780 computer. The spread deformaton of the workpiece is analyzed by means of the moire method.The calculation results are compared with experimental results of the moire and agreement is well.展开更多
In this paper, the car damper is simplified as an impulsed plate, and the dynamic deformations of the impulsed plate are measured using the moire method. The experimental method and procedures, as well as the experime...In this paper, the car damper is simplified as an impulsed plate, and the dynamic deformations of the impulsed plate are measured using the moire method. The experimental method and procedures, as well as the experimental results are discussed in detail. The good experimental results verify the feasibility of studying the damper damage procedure with the single flash dynamic moire method.展开更多
基金support from the National Natural Science Foundation of China (11372118 and 11302082)
文摘Fabrication of micro gratings using a femtosecond laser exposure system is experimentally investigated for the electron moire method. Micro holes and lines are firstly etched for parameter study. Grating profile is theoretically optimized to form high quality moire patterns. For a demonstration, a parallel grating is fabricated on a specimen of quartz glass. The minimum line width and the distance between two adjacent lines are both set to be 1 μm, and the frequency of grating is 500 lines/ram. The experimental results indicate that the quality of gratings is good and the relative error of the gratings pitch is about 1.5%. Based on molte method, scanning electron microscope （SEM） moire patterns are observed clearly, which manifests that gratings fabricated with the femtosecond laser exposure is suitable for micro scale deformation measurement.
文摘The aluminium sheet rolling is studied by using three dimensional elastic-plastic finite element method (FEM) based on considering both material and geometric non linearity.Three dimensional distribution of the stress and deformation are given on the VAX11 / 780 computer. The spread deformaton of the workpiece is analyzed by means of the moire method.The calculation results are compared with experimental results of the moire and agreement is well.
文摘In this paper, the car damper is simplified as an impulsed plate, and the dynamic deformations of the impulsed plate are measured using the moire method. The experimental method and procedures, as well as the experimental results are discussed in detail. The good experimental results verify the feasibility of studying the damper damage procedure with the single flash dynamic moire method.
