Laser forming or laser bending is a newly developed, flexible technique which modifies the curvature of sheet metal by thermal residual stresses instead of external forces. The process is influenced by many parameters such as laser parameters, material properties, and target dimensions. In this work, a pulsed Nd:YLF laser was used as the energy source. The laser beam was focused into a line shape irradiating on the stainless steel specimen to induce bending. The bending angle was measured at various processing conditions. A finite element analysis was performed with the use of a two-dimensional plane strain model to calculate the thermoelastoplastic deformation process. Experimental measurements and computational results were in good agreement. Numerical sensitivity studies were performed to evaluate the effects of the unavailable material property data at high temperature. It was found that both optical reflectivity and thermal expansion coefficient influenced the bending angle significantly, while other extrapolated material properties at high temperature yielded acceptable results.

1.
Alberti
I.
,
Franiti
L.
, and
Micari
F.
,
1994
, “
Numerical Simulation of the Laser Bending Processing by a Coupled Thermal Mechanical Analysis
,”
Laser Assisted Net Shape Engineering, Proc. of the LANE’94
, Vol.
1
, pp.
327
336
.
2.
Arnet
H.
, and
Vollertsen
F.
,
1995
, “
Extending Laser Bending for the Generation of Convex Shapes
,”
Proc. Instn. Mech. Engrs.
, Vol.
209
, pp.
433
442
.
3.
Bae
K.-Y.
, and
Na
S.-J.
,
1996
, “
An Analysis of Thermal Stress and Distortion in Bead-on-Plate Welding using laminated Isotropic Plate Theory
,”
Journal of Materials Processing Technology
, Vol.
57
, pp.
337
344
.
4.
Chen
G.
,
Xu
X.
,
Poon
C. C.
, and
Tam
A. C.
,
1998
, “
Laser-Assisted Microscale Deformation of Stainless Steels and Ceramics
,”
Optical Engineering
, Vol.
37
, pp.
2837
2842
.
5.
Geiger
M.
,
1994
, “
Synergy of Laser Material Processing and Metal Forming
,”
Annals of the CIRP
, Vol.
43
, pp.
563
570
.
6.
Lynch, D. W., and Hunter, W. R., 1985, “Comments on the Optical Constants of Metals and an Introduction to the Data for Several Metals,” Handbook of the Optical Constants of Solids, E. D. Palik, ed., Academic Press, Orlando, FL, pp. 385–396.
7.
Maykuth, D. J., 1980, Structural Alloys Handbook, Vol. 2, Metals and Ceramics Information Center, Battelle Columbus Laboratory, Columbus, OH, pp. 1–61.
8.
Namba, Y., 1986, “Laser Forming in Space,” Int. Conf. On Lasers ’85, C. P. Wang, ed., pp. 403–407.
9.
Radaj, D., 1992, Heat Effects of Welding—Temperature Field, Residual Stress, Distortion, Springer-Verlag, Berlin.
10.
Scully, K., 1987, “Laser Line Heating, “Journal of Ship Production, Vol. 3, pp. 237–246.
11.
Vollertsen, F., Geiger, M., and Li, W. M., 1993, “FDM- and FEM-Simulation of Laser Forming: A Comparative Study,” Advanced Technology of Plasticity, Z. R. Wang and Y. He, eds., International Academic Publishers, Beijing, China, PP. 1793–1798.
12.
Vollertsen, F., 1994a, “Mechanisms and Models for Laser Forming, “Laser Assisted Net Shape Engineering, Proc. of the LANE’94, Vol. 1, PP. 345–360.
13.
Vollertsen, F., 1994b, “Model for the Temperature Gradient Mechanism of Laser Bending,” Laser Assisted Net Shape Engineering, Proc. of the LANE’94, Vol. 1, PP. 371–378.
This content is only available via PDF.
You do not currently have access to this content.