论文海报模板

1、Air bending of AZ31 magnesium alloy in warm and hot forming conditionsC. Bruni, A. Forcellese, F. Gabrielli, M. SimonciniDepartment of Mechanics, Polytechnic University of Marche, Via Brecce Bianche , Ancona , ItalyCONCLUSIONS1.In all the process conditions, the forming load increases in early bendi

2、ng stage and then decreases during the final stage;2. For a given temperature, stroke and punch speed, springback decreases with decreasing punch radius;3.Springback decreases with increasing forming temperature, irrespective of the punch radius value, even though such effect is reduced with decreas

3、ing punch radius and becomes almost negligible for the smallest one investigated;DISCUSSION1.The influence of the punch radius on springback; for a given temperature and punch speed, an increase in the springback ratio with decreasing R appears.2.The punch speed can be seen that the K value is almos

4、t insensitive to v, even if a trend characterised by a slight decrease in springback with increasing punch speed.3.For a given temperature and punch radius, the volume fraction recrystallised increases with increasing punch speed.RESULTS(CONT.)nPunch speed effect on the microstructure of the bent sp

5、ecimens, R=4mm and T = 300 C: (a) v = 0.45 mm/s and (b) v = 4.5 mm/s.RESULTSnThe springback ratio increases with increasing temperature and punch radius.INTRODUCTIONOverview and importance. The effect of the process parameters on springback of AZ31 magnesium alloy was investigated by performing air

6、bending tests under warmand hot forming conditions. Magnesium alloys have been emerging as potentially candidates for several applications, in particular for lightweight structural and functional parts in the aerospace, automotive and electronic industries.Objective. To date, the mechanical properti

7、es of magnesium alloys were investigated by many researchers 115; however, no systematic study on the effect of the process parameters on springback, under warm and hot forming conditions, can be found.Reference 1. F.-K. Chen, T.-B. Huang, C.-K. Chang, Deep drawing of square cups with magnesium allo

8、y AZ31 sheets, Int. J. Mach. Tools Manuf. 43 (2003) 15531559.METHODSMaterialn AZ31 magnesium alloy was supplied in form of 3mm thick sheets,50mmin length and 27mmin width.nThe chemical composition (in wt%) of the Mg alloy is the following: 3% Al, 1% Zn, 0.2% Mn and balance Mg.Experimental proceduresnV-punch and U-die bending experiments were carried out at different temperatures ranging from 100 to 400 C, with different values of punch speed (v = 0.45 and 4.5 mm/s). nThree different V-punches, with a constant angle of 60 and nose radii (R) of 2, 4 and 6mm, were used in the ben