A secondary twinning orientation relationship between A and B martensite variants in a CuZnAl shape memory alloy was confirmed under TEM observation.The twin plane, (50),is a linear combination of (8)and(1 0 10)planes...A secondary twinning orientation relationship between A and B martensite variants in a CuZnAl shape memory alloy was confirmed under TEM observation.The twin plane, (50),is a linear combination of (8)and(1 0 10)planes,which are twin planes of A:C and A:D type pair respectively.展开更多
The effect of Ti on the microstructure and mechanical properties of zinc-aluminum ZnAl4Y alloy has been investigated in this work. Small amount of Ti was added into ZnAl4Y alloy in the form of Al-10wt.%Ti alloy. The r...The effect of Ti on the microstructure and mechanical properties of zinc-aluminum ZnAl4Y alloy has been investigated in this work. Small amount of Ti was added into ZnAl4Y alloy in the form of Al-10wt.%Ti alloy. The results show that Ti addition into ZnAl4Y alloy refines the primary η-Zn phase and increases the amount of η-Zn + α-Al eutectic structure. There exists a ternary T phase in Zn-Al-Ti alloy. Fine TiAl3 particles and Ti-Zn compounds can serve as the nucleation sites of the α-Al and η-Zn phase, respectively, resulting in the refining of the microstructure of ZnAl4Y alloy. Ti addition changes the fracture characteristics of ZnAl4Y alloy. With 0.05wt%Ti, the fracture surface of the alloy shows a lot of dimples and tearing ridges connecting the microscopic dimples, which is mainly ductile fracture morphology. Ti addition into ZnAl4Y alloy also increases the mechanical properties of the alloy. When the content of Ti is 0.05wt.%, the ZnAl4Y alloy possesses the best comprehensive mechanical properties.展开更多
The modification mechanism and damping capacity(Q-1) of conventional ascast ZA27 alloy modified by Al10%RE were investigated. Cantilever beam technique was used to measure the damping capacity. The experimental result...The modification mechanism and damping capacity(Q-1) of conventional ascast ZA27 alloy modified by Al10%RE were investigated. Cantilever beam technique was used to measure the damping capacity. The experimental results show that the addition of RE to the ZA27 alloy can refine microstructure and improve the damping capacity, the best modification effect and the highest damping capacity can be obtained at 03%RE content. It is believed that the damping mechanism of ZA27 alloy is associated with the viscous sliding or slipping of grain boundaries and interfaces, and the more the grain boundaries and interfaces, the higher the damping capacity of ZA27 alloy can be obtained.展开更多
As a part of the systematic investigation on phase relationships of Zn-Al based alloys containing Cu and/or Si, the equilibrium phase transformations of the quaternary Zn-Al-Cu-Si system at 285℃ were investigated by ...As a part of the systematic investigation on phase relationships of Zn-Al based alloys containing Cu and/or Si, the equilibrium phase transformations of the quaternary Zn-Al-Cu-Si system at 285℃ were investigated by using X-ray diffracti on, scanning electron microscopy and electron probe microanalysis techniques. A five-phase of (α+β+εT'+σ) and a four- phase of (β+ε+η+σ) were detected separately coexisting in the Zn-Al-Cu-Si system at 285℃. Then the 285℃ isothermal section of Zn-Al-Cu-Si system (with 0.1% -Si content) was established, and an equilibrium reaction was determined at 286℃ as the following pattern, β+T'=α+ε展开更多
文摘A secondary twinning orientation relationship between A and B martensite variants in a CuZnAl shape memory alloy was confirmed under TEM observation.The twin plane, (50),is a linear combination of (8)and(1 0 10)planes,which are twin planes of A:C and A:D type pair respectively.
基金financially supported by the National Natural Science Foundation of China (grant No. 51074030)
文摘The effect of Ti on the microstructure and mechanical properties of zinc-aluminum ZnAl4Y alloy has been investigated in this work. Small amount of Ti was added into ZnAl4Y alloy in the form of Al-10wt.%Ti alloy. The results show that Ti addition into ZnAl4Y alloy refines the primary η-Zn phase and increases the amount of η-Zn + α-Al eutectic structure. There exists a ternary T phase in Zn-Al-Ti alloy. Fine TiAl3 particles and Ti-Zn compounds can serve as the nucleation sites of the α-Al and η-Zn phase, respectively, resulting in the refining of the microstructure of ZnAl4Y alloy. Ti addition changes the fracture characteristics of ZnAl4Y alloy. With 0.05wt%Ti, the fracture surface of the alloy shows a lot of dimples and tearing ridges connecting the microscopic dimples, which is mainly ductile fracture morphology. Ti addition into ZnAl4Y alloy also increases the mechanical properties of the alloy. When the content of Ti is 0.05wt.%, the ZnAl4Y alloy possesses the best comprehensive mechanical properties.
文摘The modification mechanism and damping capacity(Q-1) of conventional ascast ZA27 alloy modified by Al10%RE were investigated. Cantilever beam technique was used to measure the damping capacity. The experimental results show that the addition of RE to the ZA27 alloy can refine microstructure and improve the damping capacity, the best modification effect and the highest damping capacity can be obtained at 03%RE content. It is believed that the damping mechanism of ZA27 alloy is associated with the viscous sliding or slipping of grain boundaries and interfaces, and the more the grain boundaries and interfaces, the higher the damping capacity of ZA27 alloy can be obtained.
文摘As a part of the systematic investigation on phase relationships of Zn-Al based alloys containing Cu and/or Si, the equilibrium phase transformations of the quaternary Zn-Al-Cu-Si system at 285℃ were investigated by using X-ray diffracti on, scanning electron microscopy and electron probe microanalysis techniques. A five-phase of (α+β+εT'+σ) and a four- phase of (β+ε+η+σ) were detected separately coexisting in the Zn-Al-Cu-Si system at 285℃. Then the 285℃ isothermal section of Zn-Al-Cu-Si system (with 0.1% -Si content) was established, and an equilibrium reaction was determined at 286℃ as the following pattern, β+T'=α+ε
