Phase boundary sliding model controlled by diffusion-solution zone in superplastic deformation  

作　　者：SHI Zhiqiang YE Yifu LI Shichun TENG Xinying WANG Huanrong 

机构地区：[1]Key Laboratory of Liquid Structure and Heredity of Materials of Ministry of Education,Shandong University,Jinan 250061,China [2]College of Mechanical and Electrical Engineering,University of Petroleum,Dongying 257061,China [3]College of Resource and Environment Engineering,East China University of Science and Technology,Shanghai 200237,China

出　　处：《Chinese Science Bulletin》2002年第14期1228-1232,共5页

基　　金：This work was supported by the National Natural Science Foundation of China (Grant Nos. 59871031 and 59871025).

摘　　要：With scanning electron microscope (SEM), the surface morphology of phase boundary sliding (PBS) in superplastic deformation (SPD) of Zn-Al alloy and the diffusion behavior of Zn, Al interfaces in their powers’ sintering have been investigated. The results show that Zn-Al eutec-toid microstructure can be achieved through their powders’ sintering, and the diffusion characteristic between Zn and Al is just a demonstration of Kirkendall effect, in which Zn can dissolve into Al whereas Al can hardly dissolve into Zn. During sintering, a diffusion-solution zone a’ has formed and subsequently transformed into a eutectoid microstructure in the cooling process. The superplastic deformation mechanism of Zn-Al eutectic alloy is phase boundary sliding which is controlled by the diffusion-solution zone α’. If the diffusion-solution zone α’ is unsaturated, it will have much more crystal defects and the combination between α’ and phase P is weak, thus the process of phase boundary sliding becomes easily; on theWith scanning electron microscope (SEM), the surface morphology of phase boundary sliding (PBS) in superplastic deformation (SPD) of Zn-Al alloy and the diffusion behavior of Zn, Al interfaces in their powers’ sintering have been investigated. The results show that Zn-Al eutectoid microstructure can be achieved through their powders’ sintering, and the diffusion characteristic between Zn and Al is just a demonstration of Kirkendall effect, in which Zn can dissolve into Al whereas A1 can hardly dissolve into Zn. During sintering, a diffusion-solution zone α′ has formed and subsequently transformed into a eutectoid microstructure in the cooling process. The superplastic deformation mechanism of Zn-Al eutectic alloy is phase boundary sliding which is controlled by the diffusion-solution zone α′. If the diffusion-solution zone α′ is unsaturated, it will have much more crystal defects and the combination between α′ and phase β is weak, thus the process of phase boundary sliding becomes easily; on the contrary, if the diffusion-solution zone α′ becomes thick and saturated, the sliding will be difficult.

关 键 词：ZN-AL alloy SUPERPLASTICITY phase boundary sliding (PBS) diffusion-solution ZONE (DSZ). 

分 类 号：TG111.5[金属学及工艺—物理冶金]