Influence of Process Parameters on Laser Weld Characteristics in Aluminum Alloys
Abstract
Multi-kilowatt CO2 lasers are increasingly being used for welding applications due to their capability of producing deep penetration welds at high welding speeds. Although most metals are being successfully welded, laser welding of aluminum alloys is proving to be difficult. Combination of high thermal diffusivity and optical reflectivity to CO2 laser radiation causes difficulty in coupling the laser energy to the material. Much higher laser intensities are required to ensure coupling and to form the keyhole, than to maintain the keyhole and obtain smooth fusion, as absorption of laser energy improves dramatically with the keyhole formation. Laser welds in aluminum alloys contain extensive porosity, and excessive vaporization of alloying elements occurs from the fusion zone. The welds have severe undercuts and large discontinuous cavities on the bead surface. A more precise control of the weld heat input and a better understanding of the influence of process parameters and the alloying content on the weld characteristics is required to improve the laser weldability of aluminum alloys.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1988
- Accession Number
- ADA197398
Entities
People
- Nagesh Sonti
Organizations
- Pennsylvania State University