Effect of Weld Line Direction on Tensile Deformation Behavior —Development of Forming Technology for Tailor-Welded Blank Application 2nd Report—

Abstract

The stretch flangeability of tailor-welded blank depends on the angle between weld line and the tangential line of blank edge, which is generally the tensile direction in stretch flanging. This effect was studied by uniaxial tensile testing of tailor-welded high-strength-steel specimens with a weld line at 45, 60, or 90 degrees from the tensile direction. The 60-degree-weld-line specimen provides the highest elongation at the maximum load. This is the angle at which the strain component in the weld-line direction is close to zero. At the other angles, the weld lines, of which hardness sufficiently increases by welding, play a role as a constraint for vicinal base metal. This leads to early strain localization and low elongation. Furthermore, the elongation at the maximum load can, in some cases, exceed the uniform elongation of base metal. This is pronounced by a base metal with a low n-value.

Structural and Behaviour Optimization of Tubular Structures Made of Tailor Welded Blanks by Applying Taguchi and Genetic Algorithms Methods

“…Concerning the orientation of the weld line, data showed that the springback of longitudinally welded samples is similar to that of specimens made of homogeneous materials [14,15], unlike cross-welded samples where springback decreased by about 44% in the thinner material area. The springback for thicker material is similar to one of the samples made of homogeneous material.…”