| In recent years, magnesium alloys as light structure materials have been used extensively in such fields as transport vehicles and 3C products. However, formability of magnesium alloy is poor at room temperature and many forming technologies should be processed at the higher temperature because of its hexagonal packer(HCP) crystal structure, which limits magnesium alloys applications. Therefore, the research on plastic deformation of magnesium alloys in low and moderate temperature becomes one of the hot spots on the material field. Accordingly, this paper carried out the study on deformation behavior of magnesium alloy in low and moderate temperature and hopes it have some reference value to plastic deformation of magnesium alloy.Firstly, the normal rolled AZ31 magnesium alloy sheet were prepared as the test materials in this article. The tensile properties and changes of microstructure of materials were studied in the low and moderate temperature with a different strain rate by experiment of uniaxial tension and TEM. During the experiment, temperature were selected as follows: room temperature,373K,423K,473K,523K and strain rate as follows: 10-3 s-1,0.5×10-2 s-1,10-2 s-1,0.5×10-1 s-1,10-1s-1.The experimental results show that: There is strong basal plane texture in normal rolling sheet. {1011} twinning has been proved to be the dominant model of plastic deformation at low temperature(room tmperature~423K). In addition, twinning show strong rate sensitivity and nucleation of twins grow up very quickly. With the temperature increasing, low temperature dynamic recrystallization which include twinning dynamic recrystallization and low temperature continuous dynamic recrystallization were occurred gradually and some dynamic recrystallization grains of twinning can be observed at the twinned regions. When the temperature reaches a certain degree (473~523K), dynamic recovery and continuous DRX in the deformation of tensile are triggered. The smaller of strain rate is,more fully dynamic recrystallization was carried out in order that the material was softened.Secondly, carry out the study on deformation behavior of equal channel angular rolling(ECAR) sheet of AZ31 magnesium alloy were carried out in low and moderate temperature. And then,do a comparative analysis of deformation behavior under the same conditions among normal rolling(NR) sheet and equal channel angular rolling sheet. The experimental show as follows: The texture of two sheets which have different rolling process are distinguish. The intensity of texture has been reduced afer ECAR which leads to different deformation behavior under the same conditions of deformation and reflecting the differences of macro mechanical properties. At low temperature (room temperatur~423K),the twinning still play a major role during the deformation process of equal channel angular rolling sheet. Compared to the sheets of NR, the Schmid factor of basal slip increase because of a part of grain deflecton which lead to basal slip easily started up, so the plastic of sheets were improved. As the temperature increases, a large number of continuous dynamic recrystallization grain nucleation are formed at 473K and slowly grow into equiaxed grains. When the temperature reaches a certain limits (473~523K), continuous dynamic recrystallizaion phenmena occurs obviously and the recrystallization grain that distribution like necklace nucleation in the grain boundary and grow up. The slip of magnesium alloys which restricts the occurrence of dynamic recrystallization depends on initial orientation. Compared with normal rolling sheet, the dynamic recrystallization of equal channel rolling sheet carries out more sufficiently. Plastic of equal channel rolling sheet increases and strength declines.
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