Study On Tensile Deformation Behavior Of ZE42magnesium Alloy At Elevated Temperature

In this article, which takes ZE42 magnesium alloy hot extrusion sheet for the research object, at the temperature range of 300 ℃ ~ 450 ℃, the strain rate range of0.0003 s-1~ 0.17 s-1 series of high-temperature tensile behavior, at the same time work to observe the microscopic and analysis, research the plate and high-temperature tensile deformation behavior of the deformation process of ZE42 magnesium alloy,then draw the hot processing maps, which following the important conclusions:(1) with the temperature increases the tensile strength and the yield strength of ZE42 magnesium alloy decreased, at the same strain rate, which the maximum flow stress from 220 MPa reduced to 32 MPa, elongation is increased, which occurs superplasticity phenomenon at the temperature of 450 ℃ and ? ≦0.1 s-1 of ZE42 magnesium alloy, the elongation of 109.3%, 117.3%, 143.0%, 151.1%, 155.2%,160.2% respectively.(2) the constitutive equation of ZE42 magnesium alloy under different deformation conditions at the strain value of 0.4 is as followed:RTQZ e&exp( Q = 160.8×103J/mol,which is the average of the thermalactivation energy under different conditions of temperature and strain rate)(3)The easy hot processing domain of ZE42 magnesium alloy is as followed T=380 ℃ ~ 440 ℃ and ?= 0.0003s-1 ~ 0.01 s-1.(4) high-temperature deformation mechanism changes in temperature and strain rate of change of ZE42 magnesium alloy microstructure so that is not the same after stretching. Metallographic analysis showed that, ZE42 magnesium alloys in hot tensile plastic deformation process of continuous dynamic recrystallization, climb,slide, voids and other mechanisms to gather twins.