Glass-ceramics containing β-quartz as a main crystal phase based on the system of SiO2-Al2O3-Li2O-K2O-MgO-ZnO were investigated for the application to magnetic storage substrate for higher storage capacity. Parent gl...Glass-ceramics containing β-quartz as a main crystal phase based on the system of SiO2-Al2O3-Li2O-K2O-MgO-ZnO were investigated for the application to magnetic storage substrate for higher storage capacity. Parent glasses were prepared, then nucleated and crystallized at certain temperatures for 3-4 h. The crystallization kinetics of glass-ceramics was also studied. The grain size was estimated by Scherrer formula and image treatment of transmission electron microscopy （TEM）. The results showed that the Avrami exponent was determined to be 3.88, the activation energy 189.3＋7 k J/tool and the grain size 30-60 nm. A detailed microstructure of the glass-ceramics, including grain distribution and the morphology of nano-crystalline was characterized by TEM, X-ray diffraction （XRD）, differential scanning calorimeter （DSC）, differential thermal analysis （DTA）. The relationship between microstructure and mechanical properties was also discussed.展开更多
Considering the adhesive effect and geometric nonlinearity, the adhesive contact between an elastic substrate and a clamped miniature circular plate with two different central rigid bumps under the action of uniform t...Considering the adhesive effect and geometric nonlinearity, the adhesive contact between an elastic substrate and a clamped miniature circular plate with two different central rigid bumps under the action of uniform transverse pressure and in-plane tensile force in the radial direction was analyzed. And an analytical solution is presented by using the perturbation method. The relation of surface adhesive energies with critical load to detach the contacted surfaces is obtained. In the numerical results, the effects of adhesive energy, in-plane tensile force, rigid bump size and contact radius on the critical load are discussed, and the relation of critical contact radius with the gap between the central rigid bump and the substrate for different adhesive energies is investigated.展开更多
基金The work was supported by the National Natural Science Foundation of China(Grant No.90206017)the High Tech.Program of Ministry of Science and Technology of China(Grant No.2003BA301A21)+2 种基金the Science and Technology Development Foundation of University of Shanghai(Grant No.02AK26)the Applied Materials(AM)Foundation(Grant No.0208)the Key Subject Construction Project(Material Science)of Shanghai Educational Committee.
文摘Glass-ceramics containing β-quartz as a main crystal phase based on the system of SiO2-Al2O3-Li2O-K2O-MgO-ZnO were investigated for the application to magnetic storage substrate for higher storage capacity. Parent glasses were prepared, then nucleated and crystallized at certain temperatures for 3-4 h. The crystallization kinetics of glass-ceramics was also studied. The grain size was estimated by Scherrer formula and image treatment of transmission electron microscopy （TEM）. The results showed that the Avrami exponent was determined to be 3.88, the activation energy 189.3＋7 k J/tool and the grain size 30-60 nm. A detailed microstructure of the glass-ceramics, including grain distribution and the morphology of nano-crystalline was characterized by TEM, X-ray diffraction （XRD）, differential scanning calorimeter （DSC）, differential thermal analysis （DTA）. The relationship between microstructure and mechanical properties was also discussed.
基金Project supported by the National Natural Science Foundation of China (No. 10572049).
文摘Considering the adhesive effect and geometric nonlinearity, the adhesive contact between an elastic substrate and a clamped miniature circular plate with two different central rigid bumps under the action of uniform transverse pressure and in-plane tensile force in the radial direction was analyzed. And an analytical solution is presented by using the perturbation method. The relation of surface adhesive energies with critical load to detach the contacted surfaces is obtained. In the numerical results, the effects of adhesive energy, in-plane tensile force, rigid bump size and contact radius on the critical load are discussed, and the relation of critical contact radius with the gap between the central rigid bump and the substrate for different adhesive energies is investigated.
