The Al-Mg-Mn alloy sheets with and without trace Sc and Zr were investigated by means of tensile test,X-ray diffraction,optical microscope,and transmission electron microscope.The indexes of in-plane anisotropy(IIPA)o...The Al-Mg-Mn alloy sheets with and without trace Sc and Zr were investigated by means of tensile test,X-ray diffraction,optical microscope,and transmission electron microscope.The indexes of in-plane anisotropy(IIPA)of their tensile mechanical properties were calculated and their inverse pole figures were obtained by Harris method.The two alloy sheets have the same law of in-plane anisotropy and remarkable in-plane anisotropy of mechanical properties,and the IIPA of the alloy sheet with Sc and Zr is bigger than that of the alloy sheet without Sc and Zr.The relationships of the in-plane anisotropy and the anisotropy of the crystallographic texture were analyzed based on the model of monocrystal.It is the common action of the anisotropy of crystallography and microstructures that causes the in-plane anisotropy of their mechanical properties,but the major cause is the{110}〈112〉crystallographic texture.The trace Sc and Zr can promote the formation and stabilization of the{110}〈112〉texture,inhibit the formation of the{100}〈001〉texture,and increase the in-plane anisotropy of the alloy sheet containing trace Sc and Zr.展开更多
To quest for the best combination of mechanical properties and exfoliation corrosion resisting property of Al-Mg-Mn base alloys, and to seek after the effect of Sc and Zr on mechanical and exfoliation corrosion proper...To quest for the best combination of mechanical properties and exfoliation corrosion resisting property of Al-Mg-Mn base alloys, and to seek after the effect of Sc and Zr on mechanical and exfoliation corrosion properties of Al-Mg-Mn alloys, comparative research technique was used, the mechanical properties of Al-Mg-Mn alloys with and without minor Sc and Zr treated by different annealing were measured, the degrees of exfoliation corrosion for these alloys through accelerated exfoliation corrosion test were evaluated, and polarization curves of these alloys were measured, too. The micro-morphologies of corrosion specimens were observed by SEM and the corrosion product was analyzed using EDS. Optical microscope and TEM were used, the relationship between their microstruc-tures and mechanical properties, exfoliation corrosion resisting property was investigated, and the results show that the addition of minor Sc and Zr can enhance the strength greatly and also improve the combination of strength and plasticity. Moreover, the addition of minor Sc, Zr does not cause appreciable decrease of exfoliation corrosion resisting property, the Al-Mg-Mn-Sc-Zr alloy annealed at 350 ℃ for 1 h has excellent combination of mechanical properties and exfoliation corrosion resisting property, the satisfied combination of mechanical properties nad exfoliation corrosion resisting property can be obtained by means of adding minor Sc and Zr, decreasing the content of Mn, and adopting reasonable annealing practice.展开更多
Mechanism,condition and characteristics for the formation of the network structure in a group of Zr-Al-Ni-Cu bulk metallic glasses(BMGs) were investigated.The results show that the constituent segregation and/or the s...Mechanism,condition and characteristics for the formation of the network structure in a group of Zr-Al-Ni-Cu bulk metallic glasses(BMGs) were investigated.The results show that the constituent segregation and/or the symplastic growth would be the mechanisms for the formation of the cell structure in the present Zr-Al-Ni-Cu BMGs.The cell structure can be easily obtained for the glass forming alloys whose compositions locate nearby the eutectic point.The shorter the distance is from the eutectic point,the larger the cell and the thicker the cell wall of the network structure will be.The present investigation would provide useful information for the development of the BMG with the network structure.展开更多
Objective The MicroTCA.4(MTCA.4)standard systems have been widely used in large-scale scientific facilities such as synchrotron radiation light sources and FELs over the world,covering RF control,beam instrumentation,...Objective The MicroTCA.4(MTCA.4)standard systems have been widely used in large-scale scientific facilities such as synchrotron radiation light sources and FELs over the world,covering RF control,beam instrumentation,timing,machine protection,and so on.The MTCA.4 module management controller(MMC)realizes intelligent management of the boards in the chassis through bus protocol and system interaction.It is an important functional module in MTCA.4 standard system.Methods In order to meet the requirements of the large scientific facilities,an MMC module was designed and developed.This design can realize power management of Advanced Mezzanine Card(AMC)and Rear Transition Module(RTM)boards,as well as monitoring the temperature,voltage,and current during operation.The core part of this module is limited into an area of 3 cm 3 cm on the AMC board,leaving large space for subsequent development of functional circuit.Results An AMC board was developed to verify functions of the MMC.Test results indicate that this board is compatible with existing MTCA.4 standard system.Conclusions This MMC solution can be directly and modularly applied to the design of MTCA.4 standard hardware.展开更多
基金This work was financially supported by the National Key Fundamental Research Development Program(No.G1999064911).
文摘The Al-Mg-Mn alloy sheets with and without trace Sc and Zr were investigated by means of tensile test,X-ray diffraction,optical microscope,and transmission electron microscope.The indexes of in-plane anisotropy(IIPA)of their tensile mechanical properties were calculated and their inverse pole figures were obtained by Harris method.The two alloy sheets have the same law of in-plane anisotropy and remarkable in-plane anisotropy of mechanical properties,and the IIPA of the alloy sheet with Sc and Zr is bigger than that of the alloy sheet without Sc and Zr.The relationships of the in-plane anisotropy and the anisotropy of the crystallographic texture were analyzed based on the model of monocrystal.It is the common action of the anisotropy of crystallography and microstructures that causes the in-plane anisotropy of their mechanical properties,but the major cause is the{110}〈112〉crystallographic texture.The trace Sc and Zr can promote the formation and stabilization of the{110}〈112〉texture,inhibit the formation of the{100}〈001〉texture,and increase the in-plane anisotropy of the alloy sheet containing trace Sc and Zr.
文摘To quest for the best combination of mechanical properties and exfoliation corrosion resisting property of Al-Mg-Mn base alloys, and to seek after the effect of Sc and Zr on mechanical and exfoliation corrosion properties of Al-Mg-Mn alloys, comparative research technique was used, the mechanical properties of Al-Mg-Mn alloys with and without minor Sc and Zr treated by different annealing were measured, the degrees of exfoliation corrosion for these alloys through accelerated exfoliation corrosion test were evaluated, and polarization curves of these alloys were measured, too. The micro-morphologies of corrosion specimens were observed by SEM and the corrosion product was analyzed using EDS. Optical microscope and TEM were used, the relationship between their microstruc-tures and mechanical properties, exfoliation corrosion resisting property was investigated, and the results show that the addition of minor Sc and Zr can enhance the strength greatly and also improve the combination of strength and plasticity. Moreover, the addition of minor Sc, Zr does not cause appreciable decrease of exfoliation corrosion resisting property, the Al-Mg-Mn-Sc-Zr alloy annealed at 350 ℃ for 1 h has excellent combination of mechanical properties and exfoliation corrosion resisting property, the satisfied combination of mechanical properties nad exfoliation corrosion resisting property can be obtained by means of adding minor Sc and Zr, decreasing the content of Mn, and adopting reasonable annealing practice.
基金supported by the National Natural Science Foundation of China(Grant No.50874045)Key Construction Discipline of Hunan Province
文摘Mechanism,condition and characteristics for the formation of the network structure in a group of Zr-Al-Ni-Cu bulk metallic glasses(BMGs) were investigated.The results show that the constituent segregation and/or the symplastic growth would be the mechanisms for the formation of the cell structure in the present Zr-Al-Ni-Cu BMGs.The cell structure can be easily obtained for the glass forming alloys whose compositions locate nearby the eutectic point.The shorter the distance is from the eutectic point,the larger the cell and the thicker the cell wall of the network structure will be.The present investigation would provide useful information for the development of the BMG with the network structure.
基金funded by the National Natural Science Foundation of China(No.11675174,No.11805219).Author informa。
文摘Objective The MicroTCA.4(MTCA.4)standard systems have been widely used in large-scale scientific facilities such as synchrotron radiation light sources and FELs over the world,covering RF control,beam instrumentation,timing,machine protection,and so on.The MTCA.4 module management controller(MMC)realizes intelligent management of the boards in the chassis through bus protocol and system interaction.It is an important functional module in MTCA.4 standard system.Methods In order to meet the requirements of the large scientific facilities,an MMC module was designed and developed.This design can realize power management of Advanced Mezzanine Card(AMC)and Rear Transition Module(RTM)boards,as well as monitoring the temperature,voltage,and current during operation.The core part of this module is limited into an area of 3 cm 3 cm on the AMC board,leaving large space for subsequent development of functional circuit.Results An AMC board was developed to verify functions of the MMC.Test results indicate that this board is compatible with existing MTCA.4 standard system.Conclusions This MMC solution can be directly and modularly applied to the design of MTCA.4 standard hardware.
