A penny-shaped interfacial crack between dissimilar magnetoelectroelastic layers subjected to magnetoelectromechanical loads is investigated,where the magnetoelectrically impermeable crack surface condition is adopted...A penny-shaped interfacial crack between dissimilar magnetoelectroelastic layers subjected to magnetoelectromechanical loads is investigated,where the magnetoelectrically impermeable crack surface condition is adopted. By using Hankel transform technique,the mixed boundary value problem is firstly reduced to a system of singular integral equations,which are further reduced to a system of algebraic equations. The field intensity factors and energy release rate are finally derived. Numerical results elucidate the eects of crack configuration,electric and/or magnetic loads,and material parameters of the magnetoelectroelastic layers on crack propagation and growth. This work should be useful for the design of magnetoelectroelastic composite structures.展开更多
This paper presents a new fabrication process for the SOI-based novel miniature electric field sensor. This new process uses polyimide film to release the SiO_2 layer.Compared with the CO_2 critical point release meth...This paper presents a new fabrication process for the SOI-based novel miniature electric field sensor. This new process uses polyimide film to release the SiO_2 layer.Compared with the CO_2 critical point release method,it significantly improves the device surface cleanliness and shortens the process flow.The impurity on the base layer is analyzed.The problem of peak and butterfly-type contamination occurring on the base layer of the SOI wafer during the DRIE process is discussed and solved by thickening the photoresist layer and coating with polyimide film twice.This new process could fabricate MEMS sensors and actuators such as SOI-based electric field sensors,gyroscopes,and micro mirrors and can be an alternative fabrication process compared to commercial SOIMUMPS fabrication processes.展开更多
基金supported by the National Natural Science Foundation of China (10772123)the Natural Science Fund for Outstanding Younger of Hebei Province of China (A2009001624)
文摘A penny-shaped interfacial crack between dissimilar magnetoelectroelastic layers subjected to magnetoelectromechanical loads is investigated,where the magnetoelectrically impermeable crack surface condition is adopted. By using Hankel transform technique,the mixed boundary value problem is firstly reduced to a system of singular integral equations,which are further reduced to a system of algebraic equations. The field intensity factors and energy release rate are finally derived. Numerical results elucidate the eects of crack configuration,electric and/or magnetic loads,and material parameters of the magnetoelectroelastic layers on crack propagation and growth. This work should be useful for the design of magnetoelectroelastic composite structures.
基金supported by the National High Technology Research and Development Program of China(No.2011AA040405)the National Natural Science Foundation of China(Nos.61101049,61201078)
文摘This paper presents a new fabrication process for the SOI-based novel miniature electric field sensor. This new process uses polyimide film to release the SiO_2 layer.Compared with the CO_2 critical point release method,it significantly improves the device surface cleanliness and shortens the process flow.The impurity on the base layer is analyzed.The problem of peak and butterfly-type contamination occurring on the base layer of the SOI wafer during the DRIE process is discussed and solved by thickening the photoresist layer and coating with polyimide film twice.This new process could fabricate MEMS sensors and actuators such as SOI-based electric field sensors,gyroscopes,and micro mirrors and can be an alternative fabrication process compared to commercial SOIMUMPS fabrication processes.
