Modern cars increasingly are equipped with advanced driver-assistance systems, a trend that is accelerating demand for plastic housings to accommodate electronic parts and components such as sensors, antennas, and control units. Laser transmission welding is becoming popular as a joining method during the production of these housings.
Consequently, Lanxess is upgrading its technical center in Dormagen, Germany, with a laser welding machine featuring an extensive range of equipment and state-of-the-art technology from PolyMerge GmbH, a provider of welding machines for plastics based in Geretsried, Germany. “With this highly versatile equipment, we want to develop new laser-welding materials and make them series-ready more quickly. We will also be able to emulate our customers’ production environment and help them more quickly and with tighter focus,” says Frank Krause, an expert in plastics joining processes in the High Performance Materials (HPM) business unit at Lanxess.
Laser transmission welding involves passing a laser beam through a laser-transparent component. The beam is then absorbed by a second, usually carbon black, component underneath. The beam’s energy causes localized melting on the surface of the second component. The heat generated by the process plasticizes the surface of the first component, as well, forming a material weld.
The procedure is normally used for welding covers onto housings. Compared with traditional joining techniques such as vibration and ultrasonic welding, the advantage of laser transmission welding is that the electronic components in the housing are subjected to almost no thermal or mechanical stress. Krause notes: “It also enables very small components with complex geometries to be mass-produced cost-efficiently and, therefore, meets the growing trend toward miniaturization of electrical and electronic functions.” The new machine uses an ytterbium fiber laser with a wavelength range of 1,080 nanometers and 300 watts of power.
Lanxess has already developed test specimens that can be used to reproduce typical conditions during the laser transmission welding of small and large electronics housings to define, for example, the weld line geometry and wall thickness of the translucent component. “These test specimens allow us to help our customers with many sorts of questions and problems. But we’re also supporting them with a range of additional laser-welding-related services such as simulation-based warpage optimization designed to make joining processes safer and more stable,” says Krause.
Lanxess will showcase these and other developments at K 2022 in Düsseldorf, Germany, on Oct. 19 to 26, 2022. The company will exhibit in booth C 76-78 in hall 6.