The bonding of β″-Al2O3 and pyrex glass to A1 matrix composites by anodic bonding process is achieved. The microstructure of the bonded interface and the joining mechanisms are analyzed with scanning electron micros...The bonding of β″-Al2O3 and pyrex glass to A1 matrix composites by anodic bonding process is achieved. The microstructure of the bonded interface and the joining mechanisms are analyzed with scanning electron microscope (SEM), energy dispersive X-ray fluorescence spectrometer (EDX). It is observed that the bonding region across the interface consists of the metal layer, oxide transitional layer and the ceramic layer, with the transitional layer composed of surface region and sub-surface region. The bonding process can mainly be categorized into anodic bonding process and solid state diffusing process. The pile-up of the ions and its drift in the interface area are the main reasons for anode oxidation and joining of the interface. The temperature, voltage and the drift ions in the ceramic or glass during the bonding process are the essential conditions to solid state diffusing and oxide bonding at the interface. The voltages, temperature, pressure as well as the surface state are the main factors that influence the anodic bonding.展开更多
Residual stresses and deformation of static bonding multi-layer Pyrex7740 glass and aluminum have important effects on performances of bonding parts. The stress and strain finite element analysis of anodic bonding can...Residual stresses and deformation of static bonding multi-layer Pyrex7740 glass and aluminum have important effects on performances of bonding parts. The stress and strain finite element analysis of anodic bonding can optimize the structure and process design, reduce the workload of the experiments, shorten the production cycle, improve the bonding quality, and reduce the process costs. In this paper, residual stresses and deformation in the static bonding two-layer (glass/aluminum), three-layer (glass/aluminum/ glass),five-layer(glass/aluminum/glass/aluminum/glass)and seven-layer (glass/aluminum/glass/aluminum/glass/ aluminum/glass) samples have been analyzed using nonlinear finite element simulation software MARC. The simulation results show that the shear stress distribution and deformation distribution in different multi-layer glass and aluminum samples are similar. The stress distribution along thickness at different typical positions in all multi-layer samples has characteristics of pulse pattern, which has pulse peak at the position of transition layers and then decreases abruptly to the minimum value at the positions of glass and aluminum. The maximum shear stress is located in the outside surface area in the transition layer between the top unconstrained glass layer and aluminum layer. The displacement distribution along thickness in all multi-layer samples increases gradually fi'om the constrained bottom glass layer to the top unconstrained glass layer with abrupt step increase in the aluminum layers, The maximum deformations occur in aluminum layers. It is found that the minimum deformation distortion and the minimum shear stress occur in the three-layer static bonding sample.展开更多
Pyrex glasses with different ZnS: Mn^(2+) contents were prepared by melting method. It has been found that Mn ion may occupy two sites: (Mn^(2+) )sub and (Mn^(2+) )int from photoluminescene (PL) and photoluminescence ...Pyrex glasses with different ZnS: Mn^(2+) contents were prepared by melting method. It has been found that Mn ion may occupy two sites: (Mn^(2+) )sub and (Mn^(2+) )int from photoluminescene (PL) and photoluminescence excitation (PLE) spectra. The results were confirmed by the further electron paramagnetic resonance (EPR) experiments and the three types of states (Mn^(2+) )sub, (Mn^(2+) )int and Mn clusters were identified. It was observed that the g-factor and the hyperfine structure (HFS) constant increase with the decreasing size of nanocrystallite. This may result from hybridization of sp3 electron states of ZnS and 3d5 electron states of Mn by the effects of quantum confinement and the surface states.展开更多
基金National Natural Science Foundation of China (No.50375105,No. 50671070)
文摘The bonding of β″-Al2O3 and pyrex glass to A1 matrix composites by anodic bonding process is achieved. The microstructure of the bonded interface and the joining mechanisms are analyzed with scanning electron microscope (SEM), energy dispersive X-ray fluorescence spectrometer (EDX). It is observed that the bonding region across the interface consists of the metal layer, oxide transitional layer and the ceramic layer, with the transitional layer composed of surface region and sub-surface region. The bonding process can mainly be categorized into anodic bonding process and solid state diffusing process. The pile-up of the ions and its drift in the interface area are the main reasons for anode oxidation and joining of the interface. The temperature, voltage and the drift ions in the ceramic or glass during the bonding process are the essential conditions to solid state diffusing and oxide bonding at the interface. The voltages, temperature, pressure as well as the surface state are the main factors that influence the anodic bonding.
基金Supported by the National Natural Science Foundation of China(No.51275332)Shanxi Graduate Outstanding Innovative Projects(No.20123104)
文摘Residual stresses and deformation of static bonding multi-layer Pyrex7740 glass and aluminum have important effects on performances of bonding parts. The stress and strain finite element analysis of anodic bonding can optimize the structure and process design, reduce the workload of the experiments, shorten the production cycle, improve the bonding quality, and reduce the process costs. In this paper, residual stresses and deformation in the static bonding two-layer (glass/aluminum), three-layer (glass/aluminum/ glass),five-layer(glass/aluminum/glass/aluminum/glass)and seven-layer (glass/aluminum/glass/aluminum/glass/ aluminum/glass) samples have been analyzed using nonlinear finite element simulation software MARC. The simulation results show that the shear stress distribution and deformation distribution in different multi-layer glass and aluminum samples are similar. The stress distribution along thickness at different typical positions in all multi-layer samples has characteristics of pulse pattern, which has pulse peak at the position of transition layers and then decreases abruptly to the minimum value at the positions of glass and aluminum. The maximum shear stress is located in the outside surface area in the transition layer between the top unconstrained glass layer and aluminum layer. The displacement distribution along thickness in all multi-layer samples increases gradually fi'om the constrained bottom glass layer to the top unconstrained glass layer with abrupt step increase in the aluminum layers, The maximum deformations occur in aluminum layers. It is found that the minimum deformation distortion and the minimum shear stress occur in the three-layer static bonding sample.
基金Project supported by the National Natural Science Foundation of ChinaLaboratory of Excited State Processes, Chinese Academy of Sciences
文摘Pyrex glasses with different ZnS: Mn^(2+) contents were prepared by melting method. It has been found that Mn ion may occupy two sites: (Mn^(2+) )sub and (Mn^(2+) )int from photoluminescene (PL) and photoluminescence excitation (PLE) spectra. The results were confirmed by the further electron paramagnetic resonance (EPR) experiments and the three types of states (Mn^(2+) )sub, (Mn^(2+) )int and Mn clusters were identified. It was observed that the g-factor and the hyperfine structure (HFS) constant increase with the decreasing size of nanocrystallite. This may result from hybridization of sp3 electron states of ZnS and 3d5 electron states of Mn by the effects of quantum confinement and the surface states.