The effect of the drawbead dimensions on the weld-line movements in the deep drawing of tailor-welded blanks

Tailor-welded blanks made by the laser welding process with different thickness combinations were applied in the deep drawing process without drawbeads to investigate their forming behavior. The purpose of this study is to investigate quantitatively the effects of the drawbead dimensions on the weld-line movements in the deep drawing of the tailor-welded blanks. Square blanks have been used and five different circular drawbeads of 0.0, 1.5, 2.0, 3.0, 4.0, 5.0 mm radius and also no drawbead were installed in the blank holder in the experimental apparatus. The differences in the weld-line movements and the tendencies of the thickness strain distributions were investigated by experimental and numerical methods. The results of the weld-line movement show that the smaller the radius of the drawbead installed, the larger are the values of the movements. Also it is shown that for thickness strain along the central and diagonal direction that the larger is the dimension of the drawbead, the larger are the values of maximum thickness strain. The drawbead adds additional restraining forces to the blank, hence the movement of the weld line could be controlled by adequate drawbead installation. (C) 2001 Published by Elsevier Science B.V.