After solution treatment, the 1420 Al-Li alloy samples were aged at different temperatures in an electric field with different intensity. The measurements made showed that the electric field increased the strength of ...After solution treatment, the 1420 Al-Li alloy samples were aged at different temperatures in an electric field with different intensity. The measurements made showed that the electric field increased the strength of the 1420 Al-Li alloy, and best properties were obtained when they were aged at 120 ℃ with E=4 kV/cm for 12 hrs. The electric field promoted the nucleation of δ′ phase, increased the quantity of the δ′ phase, and made the size of the δ′ phase particles smaller. The electric field restrained the formation and growth of PFZ, and increased the intensity of the electric field while the width of the PFZ was decreased.展开更多
The sliding wear behavior of hypoeutectic, eutectic and hypereutectic Al - Si alloys under lubricating condition was investigated. The wear mechanism of three kinds of alloys was discussed and an effective way to impr...The sliding wear behavior of hypoeutectic, eutectic and hypereutectic Al - Si alloys under lubricating condition was investigated. The wear mechanism of three kinds of alloys was discussed and an effective way to improve the wear reslstance of Al - Si alloys was put forward, that is increasing the silicon content.展开更多
Hypereutectic Al -27Si alloys were joined without flux by ultrasonic-assisted soldering at 420 ℃ in air using Zn -5Al the filler alloys, and Si particulate-reinforced Zn - Al based composites filler joints were obtai...Hypereutectic Al -27Si alloys were joined without flux by ultrasonic-assisted soldering at 420 ℃ in air using Zn -5Al the filler alloys, and Si particulate-reinforced Zn - Al based composites filler joints were obtained. The ultrasonic vibration introduced into soldering could influence the migration of Si particles and the microstructure of solidified Zn - Al based alloys. Both the distribution of Si particles and microstructure of the solidified Zn - Al based alloys affected the shear strength of joints. The shear strength increased with the ultrasonic vibration time. The highest average shear strength of joints reached to -68.5 MPa. Transcrystalline rupture mode was observed on the fracture surface.展开更多
A computer system for displacement sensor is developed to obtain the real-time curve of the liquid porosity of molten Al alloy foam. The relationship between the curve ofP I-t and the change of the shape of the cells ...A computer system for displacement sensor is developed to obtain the real-time curve of the liquid porosity of molten Al alloy foam. The relationship between the curve ofP I-t and the change of the shape of the cells (spherical, similar spherical and polygonal) in the foaming process is analyzed. The changes of cell diameter and cell wall thickness are studied. And the the controlling methods of a new Al alloy foam with spherical pores, low porosity and high strength are developed on this basis. Also, the stress-strain curve during compressive deformation and energy absorption characteristics are investigated and compared with polygonal pore Al alloy foam with high porosity. Keywords spherical pore - low porosity - high strength - interface shifting - Al alloy foam These authors contributed equally to this work.展开更多
文摘After solution treatment, the 1420 Al-Li alloy samples were aged at different temperatures in an electric field with different intensity. The measurements made showed that the electric field increased the strength of the 1420 Al-Li alloy, and best properties were obtained when they were aged at 120 ℃ with E=4 kV/cm for 12 hrs. The electric field promoted the nucleation of δ′ phase, increased the quantity of the δ′ phase, and made the size of the δ′ phase particles smaller. The electric field restrained the formation and growth of PFZ, and increased the intensity of the electric field while the width of the PFZ was decreased.
文摘The sliding wear behavior of hypoeutectic, eutectic and hypereutectic Al - Si alloys under lubricating condition was investigated. The wear mechanism of three kinds of alloys was discussed and an effective way to improve the wear reslstance of Al - Si alloys was put forward, that is increasing the silicon content.
基金sponsored by the National Natural Science Foundation of China(Grant No.51504165)the Project funded by the China Postdoctoral Science Foundation(Grant No.2016M601271)Tianjin Scince&Technology Project(Grant No.16JCQNJC02600)
文摘Hypereutectic Al -27Si alloys were joined without flux by ultrasonic-assisted soldering at 420 ℃ in air using Zn -5Al the filler alloys, and Si particulate-reinforced Zn - Al based composites filler joints were obtained. The ultrasonic vibration introduced into soldering could influence the migration of Si particles and the microstructure of solidified Zn - Al based alloys. Both the distribution of Si particles and microstructure of the solidified Zn - Al based alloys affected the shear strength of joints. The shear strength increased with the ultrasonic vibration time. The highest average shear strength of joints reached to -68.5 MPa. Transcrystalline rupture mode was observed on the fracture surface.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.50231010,50081002,90205005 and 19982001).
文摘A computer system for displacement sensor is developed to obtain the real-time curve of the liquid porosity of molten Al alloy foam. The relationship between the curve ofP I-t and the change of the shape of the cells (spherical, similar spherical and polygonal) in the foaming process is analyzed. The changes of cell diameter and cell wall thickness are studied. And the the controlling methods of a new Al alloy foam with spherical pores, low porosity and high strength are developed on this basis. Also, the stress-strain curve during compressive deformation and energy absorption characteristics are investigated and compared with polygonal pore Al alloy foam with high porosity. Keywords spherical pore - low porosity - high strength - interface shifting - Al alloy foam These authors contributed equally to this work.
