By: Brian Victor
With increasing material costs and competition, the need for high-productivity welding processes in manufacturing is greater than ever. Hybrid welding, increasingly referred to as HLAW (hybrid laser-arc welding), is a high productivity welding process that combines laser welding and gas metal arc welding (GMAW) in the same weld pool. This combination results in a synergy that incorporates the benefits of each individual process:
- Higher travel speeds and deeper penetration than conventional GMAW
- Lower heat input and less distortion than arc welding
- Less filler metal usage for a given thickness and smaller melt volume than arc welding
- Greater gap tolerance than autogenous laser welding
- Alloying addition and joint filling that is not possible with autogenous laser welding
For thin-sheet applications, the laser process stabilizes the hybrid weld pool enabling travel speeds of 5 m/min (200 ipm) or greater without the humping defects that usually occur in high-speed GMAW-only welding [Figure 1]. For thick-section applications, the laser keyhole process provides deep penetration through a zero-gap butt joint [Figure 2]. In both cases, the GMAW system supplies joint filling and alloy addition. Numerous alloy systems in various applications and industries can benefit from hybrid welding.
- Nickel / Inconel
- Heavy Manufacturing
- Oil and Gas
Recent hybrid work at EWI has encompassed mild and high strength steel, titanium, and aluminum. With 10kW of laser power, the hybrid process can penetrate a 0.50-in. steel square-butt joint in a single pass at approximately 2 m/min (80 ipm). Under EWI’s Cooperative Research Program (CRP) last year, hybrid welding of steel was investigated to determine the effects of multiple process variables including focal position, beam to wire distance, root shielding gas, and process orientation. Also, a custom illumination system was developed for high speed video to evaluate the process during welding [Figure 3]. As part of this year’s CRP work, mechanical properties of thick-section HSLA 100 hybrid welds will be evaluated in addition to thick-section and high-speed hybrid welding of steel, aluminum and titanium.
The above brief overview was extracted from its original abstract and paper presented at The International Congress on Applications of Lasers & Electro-Optics (ICALEO) in Orlando, FL. To order a copy of the complete proceedings from this conference click here