| Finite element analyses of simulative TWB forming operations were performed to determine the effects of weld modeling techniques. Finite element models of tailor-welded blanks were created that either included a detailed representation of the weld properties and geometry or included only a relatively simple representation that did not capture either the geometry or the material properties of the weld. In all models, shell elements were used to represent parent TWB materials. The models including weld properties and geometry used solid elements for the weld materials, and a novel method for joining shells to solids. The model excluding weld properties used nodal rigid bodies to join the thin and thick parent materials. Simulations were performed for the following metal forming tests: ASTM Tensile Test; In-plane Plane Strain Test; and several LDH tests representing variations in biaxial strain states including uniaxial tension, plane strain and biaxial tension. The results of the simulations indicated that subtle differences in the distributions of effective plastic strain, failure displacements (including overall displacement for pulled specimens, and punch travel causing failure for LDH specimens) and weld displacements at failure, existed between models including and models excluding weld properties. |
