We use the ferromagnetic resonance(FMR)method to study the properties of ferromagnetic thin film,in which external stress anisotropy,fourfold anisotropy and uniaxial anisotropy are considered.The analytical expression...We use the ferromagnetic resonance(FMR)method to study the properties of ferromagnetic thin film,in which external stress anisotropy,fourfold anisotropy and uniaxial anisotropy are considered.The analytical expressions of FMR frequency,linewidth and the imaginary part of magnetic susceptibility are obtained.Our results reveal that the FMR frequency and the imaginary part of magnetic susceptibility are distinctly enhanced,and the frequency linewidth or field linewidth are broadened due to a strong external stress anisotropy field.The hard-axis and easy-axis components of magnetization can be tuned significantly by controlling the intensity and direction of stress and the in-plane uniaxial anisotropy field.展开更多
Biodegradable orthopedic materials(BOMs)are used in rehabilitation and reconstruction of fractured tissues.The response of BOMs to the combined action of physiological stress and corrosion is an important issue in viv...Biodegradable orthopedic materials(BOMs)are used in rehabilitation and reconstruction of fractured tissues.The response of BOMs to the combined action of physiological stress and corrosion is an important issue in vivo since stress-assisted degradation and cracking are common.Although the degradation behavior and kinetics of BOMs have been investigated under static conditions,stress effects can be very serious and even fatal in the dynamic physiological environment.Since stress is unavoidable in biomedical applications of BOMs,recent work has focused on the evaluation and prediction of the properties of BOMs under stress in corrosive media.This article reviews recent progress in this important area focusing on biodegradable metals,polymers,and ceramics.展开更多
A U-shape clamp was designed to apply stress perpendicular to the interface of Cu/Sn/Cu solder joints,and its influence on the growth behavior of Cu-Sn intermetallic compound(IMC)during thermal aging at 150℃ was inve...A U-shape clamp was designed to apply stress perpendicular to the interface of Cu/Sn/Cu solder joints,and its influence on the growth behavior of Cu-Sn intermetallic compound(IMC)during thermal aging at 150℃ was investigated.The results show that compared with the sample at general stress-free state,the growth rate of IMC under compression is faster,while that under tension is slower.Moreover,the interface between IMC and Sn is smoother under compressive stress,and the corresponding IMC grains are smaller and more uniform than that under tensile stress.According to the growth kinetic analysis,the growth of IMC under general,compressive and tensile states is all controlled by the combination of grain boundary diffusion and volume diffusion with a similar growth exponent(n≈0.4).However,external stress can affect the Ostwald ripening process of grain growth,causing a change of grain size and grain boundary density in the IMC layer.As a result,the IMC growth behavior at the interface of the solder joint will be affected by the applied external normal stress.展开更多
基金the Natural Science Foundation of Inner Mongolia of China(Grant No.2019MS01021)the Research Program of Science and Technology at Universities of Inner Mongolia Autonomous Region,China(Grant No.NJZY21454)the National Natural Science Foundation of China(Theoretical Physics)(Grant No.11947414)。
文摘We use the ferromagnetic resonance(FMR)method to study the properties of ferromagnetic thin film,in which external stress anisotropy,fourfold anisotropy and uniaxial anisotropy are considered.The analytical expressions of FMR frequency,linewidth and the imaginary part of magnetic susceptibility are obtained.Our results reveal that the FMR frequency and the imaginary part of magnetic susceptibility are distinctly enhanced,and the frequency linewidth or field linewidth are broadened due to a strong external stress anisotropy field.The hard-axis and easy-axis components of magnetization can be tuned significantly by controlling the intensity and direction of stress and the in-plane uniaxial anisotropy field.
基金This work was jointly supported by the National Natural Science Foundation of China(Grant No.31570961)Scientific Research Foundation of Graduate School of Southeast University(YBJJ1525)Hong Kong Research Grants Council(RGC)General Research Funds(GRF)No.11301215.
文摘Biodegradable orthopedic materials(BOMs)are used in rehabilitation and reconstruction of fractured tissues.The response of BOMs to the combined action of physiological stress and corrosion is an important issue in vivo since stress-assisted degradation and cracking are common.Although the degradation behavior and kinetics of BOMs have been investigated under static conditions,stress effects can be very serious and even fatal in the dynamic physiological environment.Since stress is unavoidable in biomedical applications of BOMs,recent work has focused on the evaluation and prediction of the properties of BOMs under stress in corrosive media.This article reviews recent progress in this important area focusing on biodegradable metals,polymers,and ceramics.
基金financially supported by the National Key R&D Program of China(No.2017YFB0305501)the National and Local Joint Engineering Laboratory of Advanced Electronic Packaging Materials(Shenzhen Development and Reform Commission 2017-934)。
文摘A U-shape clamp was designed to apply stress perpendicular to the interface of Cu/Sn/Cu solder joints,and its influence on the growth behavior of Cu-Sn intermetallic compound(IMC)during thermal aging at 150℃ was investigated.The results show that compared with the sample at general stress-free state,the growth rate of IMC under compression is faster,while that under tension is slower.Moreover,the interface between IMC and Sn is smoother under compressive stress,and the corresponding IMC grains are smaller and more uniform than that under tensile stress.According to the growth kinetic analysis,the growth of IMC under general,compressive and tensile states is all controlled by the combination of grain boundary diffusion and volume diffusion with a similar growth exponent(n≈0.4).However,external stress can affect the Ostwald ripening process of grain growth,causing a change of grain size and grain boundary density in the IMC layer.As a result,the IMC growth behavior at the interface of the solder joint will be affected by the applied external normal stress.
