The Influence Of Compression Deforming Times At 390℃on Microstructure And Mechanical Property Of AZ80 Magnesium Alloy

In order to find a more reasonable plastic forming technology of magnesium alloy, AZ80magnesium alloy is researched. The influence of plastic deformation on microstructure andperformance of AZ80 magnesium alloy is studied by multi-steps forming at 390℃. Theevolution of performance and microstructure of AZ80 at deformation state and the situation ofβ-Mg17Al₁₂are also analyzed respectively.Homogenization treatment should be carried out for all of the blanks at 415℃+16hbefore different time deformation, during which the cumulative strain must achieve 1.6. Apart of deformation blanks will be processed by artificial aging treatment at 170℃+36h afterthe deformation is completed. Finally through the metallographic observation, fractureanalysis and mechanical performance test at room temperature we research the microstructureand performance of AZ80 at T5 and deformation state, which has been processed by differenttime deformation at 390℃. And we get the following results.Deformation time has great influence on microstructure and properties of AZ80magnesium alloy during the deformation at 390℃, which the cumulative strain is 1.6. If it isdeformed for one or two times. although each deformation has a larger strain and a moredynamic recrystallization ratio, the final comprehensive mechanical performance will be poorbecause its microstructure is very even---there are both dynamic recrystallization and residualcoarse grains as a result of its fewer times of deformation and intermediate heating. TheDeformation by three or four times, its microstructure is very even, and the grain has alsobeen refined. At last deformation by four times obtained the best comprehensive mechanicalproperties. At the same time as the blank deformation by four times has an evenmicrostructure, after the aging treatment it gets more precipitated phase, so its aging strengthening is more obvious. But the second phase precipitation also reduce the materialplastic. Finally the blank of AZ80 at T5 state, which has taken four time deformation has thehighest strength and hardness, and the figure is respectively 355MP and HRB 49.5. But thepercentage elongation has almost no difference, and it is about 5.7% 6%.