Share Email Print
cover

Proceedings Paper

Effects of different shielding gas compositions on the process of cw CO2 laser welding in the hyperbaric range
Author(s): R. Ducharme; Phiroze D. Kapadia; C. Lampa; Anders Ivarson; J. Powell; Claes Magnusson
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

A continuous carbon-dioxide laser of 1.35 kW has been used to study the welding of 5 mm thick stainless steel for pressures ranging from 0.1 to 0.8 MPa in increments of 0.1 MPa. Experimental data, including penetration depths, weld widths, and in some cases weld pool profiles, has been obtained for each value of the pressure using different mixtures of argon and helium shielding gases. In a previous paper it has been reported that keyhole welding could not be carried out for pressures significantly in excess of atmospheric pressure using pure argon and nitrogen shielding gases, but that the process was possible at pressures up to 0.8 MPa using helium. In the present paper the critical pressure for keyhole welding is determined as a function of the mixed shielding gas composition. The laser material interaction is analyzed by solving the heat conduction equation with line and point heat sources representing the keyhole and plume respectively. The line source strength is itself calculated from consideration of the inverse bremsstrahlung and Fresnel absorption processes in the keyhole. It is concluded that successful laser welding in the hyperbaric range crucially hinges on good plume control through the effective delivery of an appropriate shielding gas mixture.

Paper Details

Date Published: 4 April 1997
PDF: 4 pages
Proc. SPIE 3092, XI International Symposium on Gas Flow and Chemical Lasers and High-Power Laser Conference, (4 April 1997); doi: 10.1117/12.270124
Show Author Affiliations
R. Ducharme, Univ. of Essex (United Kingdom)
Phiroze D. Kapadia, Univ. of Essex (United Kingdom)
C. Lampa, Lulea Univ. of Technology (Sweden)
Anders Ivarson, Lulea Univ. of Technology (Sweden)
J. Powell, Lulea Univ. of Technology (Sweden)
Claes Magnusson, Lulea Univ. of Technology (Sweden)


Published in SPIE Proceedings Vol. 3092:
XI International Symposium on Gas Flow and Chemical Lasers and High-Power Laser Conference

© SPIE. Terms of Use
Back to Top