Numerical simulation analysis of variable BHF drawing of rectangular case on curve blank-holder

Apply the method of numerical simulation,the effect to draw ability of rectangular case is researched which is based on curve blank-holder while the Blank-Holder Force(BHF)is changed with the time or displacement.The analysis result shows the gradual increase of BHF correspondingly improved the formability of rectangular case,on the contrary,the gradual decreases of that couldn′t accomplish it.In the test of simulation of drawing when the blank-holder is separated to corner and straight edge and different model of BHF is adopt,when BHF gradually increased in corner and straight edge of flange,it's improved the formability of rectangular case in a great degree.