ASSEMBLY AUTOMATION ALTERNATIVES OFFERS:
AFFORDABLE FIBER LASER WELDING THIN TO THICK MATERIALS, SIMILAR AND DISIMILAR MATERIALS
September 30, 2019
When laser welding first started to appear in production settings some three-plus decades ago, the primary attraction was its high welding speed and significantly deeper weld penetration when compared to traditional welding methods. To be sure, production laser welding systems are capable of providing welding speeds four to five times faster than traditional ARC welding. In addition, the superior penetration afforded by laser systems enables single-pass welds in situations where traditional welding would require multiple passes.
It didn’t take long, however, before some of the less obvious advantages of laser welding began to garner significant interest --- most notably, the ability of laser welding systems to effectively weld thin as well as dissimilar materials. It was customers’ increasing interest in these areas that drove Automation Alternatives to focus their engineering and product development efforts on optimizing their systems’ capabilities in these areas.
While many companies became fixated on welding ever thicker materials, others faced the more daunting challenge of welding extremely thin materials. The high welding speeds associated with laser welding systems together with the high power-densities achievable with the exceptionally small spot size --- typically .001 to .002in for the Automation Alternatives RubyLaser FLW (fiber laser welding) system --- yield comparatively small heat-affected zones. This is particularly important for thin, low-mass work pieces that do not have the ability to readily diffuse heat and are therefore susceptible to distortion.
An even thornier challenge was applications that required welding thin to much thicker materials. The disparity between the energy required to sufficiently heat the thicker versus the thinner part risked deformation of the latter or inadequate heating of the thicker part resulting in poor weld quality. When asked how Automation Alternatives addressed this dilemma, CEO Mehdi Soghrati explained that AAA developed a highly sophisticated laser controller that is capable of modulating the laser over a very wide range. He went on to say that the controller algorithm ensures that sufficiently high energy is applied to the part with the higher mass and then attenuates power and modulates pulse to accommodate the thinner part during the welding process.
The AAA controller, it turns out, is capable of regulating the laser over a significantly wider range than competitors’ systems, and is able to modulate laser power by as much as 25% allowing for welding parts as thin as 0.001in. This allows a higher-powered laser to weld thin materials that would typically be processed on a lower-powered machine. The RubyLaser FLW system is also able to produce welds of different finishes, patterns and penetration. Also, by leveraging the laser’s line-of-sight welding capability, a variety of weld geometries can be achieved that are simply beyond the capabilities of traditional welding systems.
The ability to weld thinner parts is by no means limited to just similar materials. Automation Alternatives systems are being successfully used in the welding of a range of dissimilar material pairs. One customer producing industrial sensors is running 3 AAA welding systems to join thin copper parts to a stainless sensor body. Other customers in the electronics, medical devices, and aerospace industries are using AAA systems to
produce titanium/steel, copper/nickel, and aluminum alloy/nickel welds as well as joining a variety of different steel alloys.
One of the most significant obstacles to creating high-quality welds of dissimilar materials has been the creation of intermetallics and non-homogeneous structures within the weld when the melting points of the two materials being joined diverge. This most commonly occurs when the material with the lower melting point approaches its vaporization temperature. This was a common problem with the previous generation Nd:Yag lasers. Fiber lasers, due to their smaller spot size and consequently smaller heat affected zone, are somewhat less prone to this problem overall. The ability of the Automation Alternatives controller to precisely control heat input to each material individually, however, further mitigates the creation of intermetallics during the welding process. The controller’s algorithm ‘shapes’ the laser’s power and pulse where the two molten materials mix thereby reducing the likelihood of brittle or otherwise poor weld quality --- and without the need to introduce filler metals in the vast majority of applications.
When sourcing a laser welding system, customers tend to consider a system based upon the thickest materials they expect to weld as well as their cycle-time requirements. RubyLaser FLW systems are available at power levels ranging from 450W to 5kW.
Customers who would have otherwise been drawn to EB welding systems due to the high purity of their welds and virtual absence of contaminants, find the AAA systems a more cost-effective choice in most cases. Compared to other FLW systems and especially Nd:Yag systems, the AAA laser controller significantly reduces the likelihood of intermetallics, producing welds that approach those of EB systems. In addition, EB systems require vacuum chambers of a size suitable for the assemblies being welded and the evacuation and load/unload times negatively impact cycle-time. Overall, FLW tend to be more practical for most applications.
Not constrained by vacuum chambers, the Automation Alternatives RubyLaser FLW systems have the added advantage of being available in 2x2’, 4x4’ and 4x8’ working areas and a can be equipped with a feather-touch, automatic pull-out table to facilitate loading and unloading of the machine. The ergonomics of this load/unload system are a welcome relief to laser operators that have had to work with traditional load/unload designs. In addition, systems can be equipped with single and multiple rotary axes and spindles, specialty fixtures and custom automation if desired.
Automation Alternatives FLW systems rank among the most high-precision laser welding systems available in the industry. To push the precision-envelope even further, AAA has individually configured vision systems installations for both their welding and cutting laser lines enabling unparalleled precision. With hundreds of such systems installed in the field, the reliability is unquestioned. But precision does not come at the expense of efficiency. Automation Alternatives lasers have the lowest power consumption and maintenance costs and boast a laser life well upwards of 100,000 hours.
To sum it up, Automation Alternatives is able to offer a custom solution for your specific project at less than a standard off the shelf system by tailoring the design to your particular requirements rather than providing an overall generic solution.
Canada - Automation Assembly Alternatives 905 605 9200 firstname.lastname@example.org www.auto-alt.com
USA- Laser Americas, LLC 508 989 5090 email@example.com