Laser plastic welding is a proven, powerful, and effective way to join plastics. It’s been used in industry for over 20 years and its ability to weld a wide variety of part sizes, with precision weld joints, minimal flash, and no particulate is unmatched by other welding processes.
Typically, the process uses an infrared (IR) laser that is passed through an IR-transmissive layer of plastic and is absorbed by an IR-absorptive layer beneath. This is referred to as through-transmission welding. There are multiple types of laser welding that apply the energy in a variety of ways. Simultaneous laser welding uses fiber optics to evenly distribute the laser energy along the entire weld joint all at the same time. Quasi-simultaneous moves a single laser beam along the weld joint very quickly and with many passes to create a similar effect as simultaneous. Line beam or curtain welding uses optics to spread the laser energy into a curtain that is passed over the part like a wide paintbrush. And lastly, masking uses a similar laser curtain, but with a precision-cut mask over the part to shield the areas that don’t need laser energy.
Each of these laser welding methods is carefully selected based on numerous parameters – complexity and size of part geometry, material types, strength requirements, aesthetics needs, assembly function, just to name a few. Our team understands and can educate you on the pros and cons of the various methods. They can help pair your application with the appropriate laser welding method for optimum results. Three key factors that help to identify laser welding applications are…
Precision and Accuracy – The powerful and focused energy of a laser allows for that energy to be precisely placed where it is needed; directly to the area that needs to be joined. Distributing radiant energy can be tricky but using a laser, the correct optics, and a galvanometer scanner, Extol’s laser welding system can put the energy just where you want it, and nowhere you don’t.
Flash Control – Welding plastic produces flash in all welding technologies. It’s a matter of what type of flash, how much, and how its managed. With laser plastic welding, the amount of flash can be very accurately controlled due to the precision of the energy distribution. Laser welding can also eliminate nasty particulate for a nice clean weld.
Part Size – Laser plastic welding is effective for a wide variety of parts ranging from tail lamps to key FOBs. It can be especially useful for smaller parts where other welding technologies lack the cleanliness and precision needed. In these miniature applications, weld cycle times can be sub-five seconds while still producing a precise, strong weld.
Nick is a mechanical engineer who works with Extol’s Design, Controls, Service, Applications, and Manufacturing Solutions teams. When Nick isn’t thinking about plastic joining machines, he’s cycling, boating, or hanging out with his wife and boys.