Ky. Bae et Sj. Na, A STUDY OF THE EFFECT OF PRE-STRAINING ON ANGULAR DISTORTION IN ONE-PASS FILLET WELDING INCORPORATING LARGE-DEFORMATION THEORY, Proceedings of the Institution of Mechanical Engineers. Part B, Journal of engineering manufacture, 209(5), 1995, pp. 401-409
By using the finite element method based on the large deformation theo
ry, the effect of pre-straining on angular distortion of one-pass fill
et weldments was analysed for the free-end and constrained-end conditi
on. Pre-straining by an additional concentrated load caused a large th
ermal deformation during heating, and reduced the reverse distortion d
uring cooling and consequently the residual distortion. Geometric chan
ge of the fillet weldment caused by pre-straining during welding induc
ed an initial stress effect on the stiffness to the further deformatio
n, which is due to a developed in-plane stress. This initial stress ef
fect could be considered in the large deformation theory to be based o
n the updated Lagrangian method, while it could not in the small defor
mation theory. As the pre-straining load increased in the free-end con
dition, the initial stress effect also increased. In the constrained-e
nd condition, the initial stress effect played an important role in th
e deformation of the fillet weldment, even without pre-straining. By c
omparing the results predicted by the large deformation theory with th
ose by the small deformation theory and experiments, it can be shown t
hat the large deformation theory is able to describe the distortion ph
enomenon in fillet welding reasonably well.