Shrinkage hole problem of energy storage welding

How is weld shrinkage determined experimentally?

The technique for determination of weld shrinkage described in the work involves experimental measurements using strain gauges to determine residual stresses at two points, which are at known distances from the weld.

How does hot expanded weld metal shrink volumetrically?

Hot expanded weld metal shrinks volumetrically—through the weld’s length, width and height. When welds intersect from different orthogonal directions—particularly when interesting from all three—the resultant weld shrinkage creates tri-axial stresses that limit the ability of the steel to behave in a ductile manner.

What is the maximum shrinkage deformation of a weld?

The maximum shrinkage deformation is at the weld face, which is shown as bαθs. The shrinkage deformation becomes zero at the weld root (weld penetration). The inherent shrinkage deformation area (cm 2) is shown by area o–a–b–c–d–e–o and the transverse shrinkage deformation Δ cg is shown by line a–d–f–g.

What causes a shrinkage strain in a weld?

The inherent shrinkage strains are primarily caused by material softening and nonlinear thermal gradients in the cooler areas. The inherent shrinkage strains are uniform along the weld length, except in the areas of arc start and stop. They are nearly uniform within the softening area in the direction transverse to the weld.

What is the angular shrinkage of a fillet weld?

As the interface of a fillet weld is approximately triangular, its transverse shrinkage is more significant at the weld surface than at the weld root, resulting in angular shrinkage β ″ between the web and wing plate. The size of β ″ is basically independent of the size parameter.

What causes shrinkage voids in resistance spot welds?

Among various defects formed in resistance spot welds of advanced high strength steels (AHSS), shrinkage voids are seldomly studied. Apparently, the voids are thought to be formed towards the end of solidification due to the material volumetric shrinkage.