Technology allows weight, time and money savings while optimizing aesthetics.
Since the early 2000s, laser plastics welding has been coming into its own, starting with electronics and gaining in acceptance in other key industries such as automotive. One of three non-friction welding processes, laser welding is a gentle and clean joining process that enables welding of complex geometries and materials that are difficult to bond with other techniques.
Now, Americhem, Cuyahoga Falls, Ohio, and Germany’s LPKF Laser & Electronics (U.S. office in Tualatin, Ore.) have collaborated on a laser plastic welding technology that allows manufacturers to save weight, time and money vs. using traditional materials, while maintaining and optimizing part aesthetics.Just within the first half of this year, we have reported on new laser welders from major players like Branson and Dukane, including clear-to-clear plastic welding and large format welding for complex geometry parts. Other news included Japan’s Panasonic Corp.’s Automotive Systems Company (U.S. office in Peachtree City, Ga.) announcing the development and start of mass production of PBT molding compounds for laser welding. The target: automotive switches and sensors, where these new compounds reportedly enhance design flexibility and long-term reliability.
Two plastics are joined together using laser radiation in the laser plastics welding process. The plastics being welded have a transmissive upper layer and an absorbing lower layer, allowing the laser to heat the materials in the lower layer and bond them to another compatible material.
The lower layer is often based on high-absorptive pigments such as carbon black. In their partnership of this technology, LPKF provides the production equipment and process solutions used in laser plastic welding while Americhem provides custom coloring technology for both the upper and lower layers.
In order to provide the ultimate in design aesthetics, Americhem says it can match colors in the transmissive upper layer that enable the laser to pass through this visible layer and create the laser weld using the absorbing lower layer.
This technology is gaining wide use in the automotive, medical and consumer products industries. Brett Conway, group director, plastics for Americhem gives this example of the technology’s advantage: a car taillight cover, where laser plastic welding helps ensure a tight seam. “With LPKF’s welding equipment and Americhem’s color, this seal along the top of the taillight is visible and was actually used as part of the taillight’s creative design.”
Adds LPKF President Stephen Schmidt, “Though laser plastic welding has existed over a decade, the demand has grown recently as automobile manufacturers sought better quality solutions, lightweighting, and robotic assembly in their manufacturing processes. Because of the ability to custom color most parts, the welds can match the other components in the interior or exterior of the vehicle.”