| Magnesium alloys, the potential development of metal material in the21st century,are the lightest metal structure material. They are generally classified into wroughtmagnesium alloys and cast magnesium alloys. The former can be wider used than thelatter such as aviation, spaceflight, automobile, motorcycle and other fields. In order todevelopment the magnesium industry, we must make great efforts to develop theproduce and forming process of wrought magnesium alloys.With ZK60magnesium alloy plate as research object, its high temperaturebulging behavior was systematically studied, the optimum parameters scope of hightemperature bulging of ZK60magnesium alloy plate had been confirmed.First the tensile test studied plastic deformation behavior of ZK60magnesiumalloy in the temperature of280℃,310℃,340℃,370℃,400℃and strain rate of1×10-1s-1,1×10-2s-1,1×10-3s-1,1×10-4s-1. The results showed that ZK60magnesium alloy hadgood plastic with elongation rate133.7%at370℃and strain rate of1×10-4s-1. Withstrain rate sensitive index m=0.29, high temperature bulging flow stress model ofZK60was created based on its stress-strain curve, and the process parameters of hightemperature were determined.Next, According to the bulging experiment requirements, bulging process ofZK60was simulated based on finite element analysis method, and limit Ericson Valueof ZK60magnesium alloy in370℃was got, the metal flow law and stress-strainconditions were also discussed.At last Bulging test of ZK60magnesium alloy plate were conducted between theroom temperature and high temperature. The test results showed that the Ericson Valuereached16.5mm at370℃, the Bulging highlyincreased by266.7%compared with theroom Ericson Value. The thickness of bulging become thinner with height increase gradually in the bulge forming, and the wall thickness is uneven, The annular edgeregions in contact with the plank of the punch were most easily bilge crack. The thesishas also explained the plastic deformation mechanism of the ZK60magnesium alloyboth macroscopically and microscopicallyThe results of Bulging test was basic consistent wish the numerical simulationprocess, verifying the ZK60plate magnesium alloy could proceed complex bulgingthrough the basic mechanical properties test by the numerical simulation analysis. |
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