In terms of efficiency, quality and precision, handheld laser beam welding is significantly superior to the arc welding process. However, it requires considerably higher safety standards and a thorough understanding of the process. Messer not only supplies the appropriate shielding gases but also provides the essential expertise for safe handling and optimal results.
Advantage: Energy density
Highly concentrated energy is the hallmark of the laser beam. This enables a precisely focused welding process that simultaneously minimises heat input and distortion of the workpiece. It also allows for high welding speeds with extremely simple handling: with thin sheets, high-quality welds can be achieved after only a short training period.
However, in handheld welding, the intensity of the laser beam also requires particularly thorough protection for the operator and everyone else in the vicinity. This is because the high energy density is also present in the inevitable scattered radiation. Even small amounts of scattered radiation can cause serious damage to unprotected skin and, even more so, to the eyes.
Essential safety precautions
“Helmets and safety goggles must be certified for use with handheld laser beam welding equipment,” emphasises Dr. Dirk Kampffmeyer, an expert in welding technology at Messer. “There is yet no valid standard for gloves and protective clothing. We recommend glass-fibre-reinforced fabrics, or at the very least leather.”
Equally important is the shielding of the workstation. Reliable protection for third parties is ensured by a cabin whose door is linked to the laser source, and which switches it off immediately when opened. When working behind partition walls and curtains on a construction site, one person must continuously monitor access. “Of course, the laser technology itself must also have a safety shut-off mechanism,” explains Dr. Kampffmeyer. “I strongly warn against uncertified, cheap products, which are actually banned but can unfortunately still be purchased online.”
A wide range of factors affecting weld quality
With the appropriate precautions in place and by adhering to the rules, occupational safety can be fully guaranteed. To achieve a good result, however, in-depth expertise in the process is also required, as well as shielding gases that are suitable for the material in question. The expert describes the countless test welds carried out at Messer to identify the optimal gases for laser beam welding of various metals.
From the base material through to the beam power and scan frequency, he lists eleven parameters that influence the result. “We have analysed the process in great detail across many different variants. On this basis, we can support our customers in optimising their applications. This requires, not least, precisely matched shielding gases. Messer has developed a bespoke portfolio specifically for laser beam welding.”
Bespoke gases and comprehensive advice
Lasline C, for example, helps to reduce porosity and improve penetration during laser beam welding of unalloyed materials. Ferroline X4, a mixture of argon and oxygen, speeds up the welding process. For high-alloy steels, our mixtures containing hydrogen – Inoxline H5 (argon and hydrogen) and Lasline H5 (nitrogen and hydrogen) – provide greater energy input during the welding process. Aluline He 30 is recommended by many users as the optimal solution for welding aluminum. This gas mixture of argon and helium increases the heat input and improves degassing of the weld seam.
“Over the years, Messer has built up partnerships with suppliers of safe and efficient technology. We understand the factors influencing weld quality from our own extensive research,” emphasizes Dr. Kampffmeyer. “This enables us to offer users not only gases but also comprehensive advice – ranging from detailed on-site assessment of their welding processes, through process development and technical training, to cost-effectiveness analysis.”
For more than 125 years, Messer, the today’s world's largest privately owned company for industrial gases, medical gases, specialty gases, and gases for electronics, committed to its guiding principles of safety, focus on customers and employees, responsibility for our society, sustainability, trust, and respect. Messer's Gases for Life and patented gas applications are essential for environmental protection, climate protection, decarbonization, and innovation.