In this paper,a synthesized technique is explored through design of a virtual experiment system for main aero-engine based on VR,which attempts to integrate some VR techniques,such as 3D stereo simulation and modeling...In this paper,a synthesized technique is explored through design of a virtual experiment system for main aero-engine based on VR,which attempts to integrate some VR techniques,such as 3D stereo simulation and modeling,3D scene management and human-computer virtual assembly based on data glove and collision detection.The geometry modeling and instantiation technique,virtual hand modeling and data glove interaction technique are discussed chiefly.Finally,taking aim at assembling and dismantling experiment system of a certain aero-engine,interface technology is expounded also.展开更多
Corrosion of Mg–Y alloy was studied using electrochemical evaluations, immersion tests and SEM observations. Corrosion mechanisms of Mg-（0.25 and 2.5） Y alloy and Mg-（5, 8, and 15） Y alloy were uniform corrosion ...Corrosion of Mg–Y alloy was studied using electrochemical evaluations, immersion tests and SEM observations. Corrosion mechanisms of Mg-（0.25 and 2.5） Y alloy and Mg-（5, 8, and 15） Y alloy were uniform corrosion and pitting corrosion respectively, and the content of Mg_（24）Y_5 phases determined its effect acting as cathode to accelerate the corrosion or corrosion barrier to inhibit the corrosion. Corrosion resistance of Mg-（0.25, 2.5, 5, 8, and 15） Y alloys was as follows： Rt（Mg-0.25Y） 〈 Rt（Mg-8Y） 〈 Rt（Mg-15Y） 〈 Rt（Mg-5Y） 〈 Rt（Mg-2.5Y）. Y could significantly improve the corrosion resistance of the Mg-Y alloy, but the excess of Y deteriorated the corrosion resistance of the Mg-Y alloy. The optimum content of Y in the studied alloys was 2.5%.展开更多
The influences of the hot extrusion process on the microstructure, corrosion behavior and corrosion mechanism for Mg-Y magnesium alloy were studied by means of the microstructure observation, weight loss test, electro...The influences of the hot extrusion process on the microstructure, corrosion behavior and corrosion mechanism for Mg-Y magnesium alloy were studied by means of the microstructure observation, weight loss test, electrochemical test and corrosion morphology test. The results showed that with increasing of the extrusion ratio, the shear flow line on the vertical section of the extruded alloy increased, the shear bands parallel lines became more clearly visible, and a large number of fine equiaxed grains distributed in parallel with the flow lines. The open circuit potential had a certain degree of improvement after extrusion, the open circuit potential increased with increment of extrusion ratio, and the corrosion potential of the vertical section was higher than that of the same alloy in the same compression ratio. The shift rate of the corrosion potential relatively became larger with increasing of the extrusion ratio, and the cathode corrosion current corresponding to the branch migration shifted to the positive direction. The high frequency capacitive arc increased with increment of the extrusion ratio, and the radius of capacitive arc of the vertical section was slightly larger than that of the transverse section. The corrosion morphologies of Mg-0.25 Y alloy were uniform corrosion, and the corrosion morphologies of Mg-（2.5, 5, 8 and 15） were the pitting corrosion and the small range, deep depth localized corrosion.展开更多
文摘In this paper,a synthesized technique is explored through design of a virtual experiment system for main aero-engine based on VR,which attempts to integrate some VR techniques,such as 3D stereo simulation and modeling,3D scene management and human-computer virtual assembly based on data glove and collision detection.The geometry modeling and instantiation technique,virtual hand modeling and data glove interaction technique are discussed chiefly.Finally,taking aim at assembling and dismantling experiment system of a certain aero-engine,interface technology is expounded also.
基金Funded by the National Key Technology R&D Program of China(Nos.2011BAE22B01 and 2011BAE22B06)
文摘Corrosion of Mg–Y alloy was studied using electrochemical evaluations, immersion tests and SEM observations. Corrosion mechanisms of Mg-（0.25 and 2.5） Y alloy and Mg-（5, 8, and 15） Y alloy were uniform corrosion and pitting corrosion respectively, and the content of Mg_（24）Y_5 phases determined its effect acting as cathode to accelerate the corrosion or corrosion barrier to inhibit the corrosion. Corrosion resistance of Mg-（0.25, 2.5, 5, 8, and 15） Y alloys was as follows： Rt（Mg-0.25Y） 〈 Rt（Mg-8Y） 〈 Rt（Mg-15Y） 〈 Rt（Mg-5Y） 〈 Rt（Mg-2.5Y）. Y could significantly improve the corrosion resistance of the Mg-Y alloy, but the excess of Y deteriorated the corrosion resistance of the Mg-Y alloy. The optimum content of Y in the studied alloys was 2.5%.
基金supported by the National Key Technology R&D Program of China(2011BAE22B01,2011BAE22B06)
文摘The influences of the hot extrusion process on the microstructure, corrosion behavior and corrosion mechanism for Mg-Y magnesium alloy were studied by means of the microstructure observation, weight loss test, electrochemical test and corrosion morphology test. The results showed that with increasing of the extrusion ratio, the shear flow line on the vertical section of the extruded alloy increased, the shear bands parallel lines became more clearly visible, and a large number of fine equiaxed grains distributed in parallel with the flow lines. The open circuit potential had a certain degree of improvement after extrusion, the open circuit potential increased with increment of extrusion ratio, and the corrosion potential of the vertical section was higher than that of the same alloy in the same compression ratio. The shift rate of the corrosion potential relatively became larger with increasing of the extrusion ratio, and the cathode corrosion current corresponding to the branch migration shifted to the positive direction. The high frequency capacitive arc increased with increment of the extrusion ratio, and the radius of capacitive arc of the vertical section was slightly larger than that of the transverse section. The corrosion morphologies of Mg-0.25 Y alloy were uniform corrosion, and the corrosion morphologies of Mg-（2.5, 5, 8 and 15） were the pitting corrosion and the small range, deep depth localized corrosion.
