Domo Chemicals has developed a new polyamide (PA) 66 black-colored family of plastics suitable for laser welding, a technology that is increasingly used in joining thermoplastic parts. Domo’s new laser-transparent Technyl Star AF 219 V30 black LT is now available on the market.

Laser welding is becoming one of the most cost-effective technologies to deep-weld polymer materials together in many industries and is particularly used in the development of complex and small shaped plastic parts for the automotive market, electronic circuits, Internet of Things applications, and consumer goods. The most relevant benefits of this technology include speed, flexibility, precision, and appearance. Laser welding is also a low-dust technology, a key high performance for electric and electronic applications.

“Being such a concentrated heat source, in thin materials laser welding can be carried out at high welding speeds. Thicker materials can produce narrow, deep welds between square-edged parts. Our Technyl Star AF 219 V30 black LT expanded product family will be important for the electric vehicle market, where there is growing demand for sensor boxes, cases, and control units,” explained Vincent de Givry, Marketing Director, Engineered Materials.

“There is a clear trend in the market for electro-friendly, laser-welding-compatible materials, because this clean welding technology is often used in sensitive corrosion applications. That’s why our solutions are also available in electro-friendly alternatives, making them suitable for sensitive electrical applications, while offering a cost-efficient solution,” de Givry continued.

The joining technique entails a laser beam passing through the laser-transparent part to reach the laser-absorbing component, melting the material in a localized area, and realizing contactless welding from the inside out, thereby creating a clean, invisible, and aesthetic finish. Other technologies that require friction during welding create air pollution in the process, meaning that parts require post-production cleaning.

Technyl Star AF 219 V30 black LT was measured using a light transmission test at a wavelength of 940 nm, proving the suitability of this solution at up to 3-mm thickness.

Additionally, Domo’s in-house APT part-testing service can perform burst tests on welded parts for final proof of concept and to speed the customer’s time to market. All tests to date have shown good cohesion of the welding, according to the company.

New applications for laser welding are constantly emerging. One of these is extruded tubes for air-conditioning lines, and Domo has developed an unfilled alternative that has passed the burst test before and after refrigerant aging.

Looking ahead, a reinforced PA6 30% glass-fiber, specifically designed for laser welding technology, is under development and will be released to the market shortly.