Furukawa Electric Develops Gapless Welding Technology for Zinc-plated Steel Plates for Automobiles
- Technology to help reduce manufacturing costs and increase performance for automobile bodies -

April 24, 2018

Furukawa Electric Co., Ltd. has developed “LC3W: Laser Continuous, Close Contact Welding,” a new fiber laser technology that drastically reduces welding defects that occur when welding zinc-plated steel plates(note 1) for automobiles. The technology promises to reduce manufacturing costs for automobile bodies, and to greatly improve automobile body strength.

(note 1)Zinc-plated steel plate: A steel plate that has been processed with zinc-plating. Zinc-plating functions to prevent rust, and is used for galvanized plates and materials for automobiles.


Zinc-plated steel plates are often used to add anti-rust/anti-corrosion functionality to automobile bodies. Zinc-plating evaporates around the melting point of steel plates. If lap welding is conducted to attached Zinc-plated steel plates using a fiber laser, the zinc evaporates, resulting in many welding defects.
Using current construction methods, this is normally resolved by leaving a gap of around 0.1 to 0.3 mm between steel plates in order to eliminate zinc evaporation. However, it has been difficult to fully simplify construction methods by introducing fiber lasers, due to factors such as complicated fixing jigs and limitations on manufacturing processes or material shapes.


Furukawa Electric’s Fiber Laser Application Lab has developed “LC3W: Laser Continuous, Close Contact Welding,” a new laser welding technology for continuously line-welding lapped zinc-plated steel plates for automobiles, without any gaps.
The technology uses the “high energy capacity beams” and “beam mode control technology” provided by Furukawa Electric fiber lasers to form the ideal beam mode for continuously welding attached zinc-plated steel plates, dramatically reducing welding defects.
Resistance welding, the current welding method, uses spot-welding. There is a limit to the number of welding points that can be used, restricting the degree to which vehicle bodies can be strengthened. LC3W makes continuous line-welding possible, greatly helping to improve vehicle body strength and design flexibility. As there is no longer any need to control gaps between steel plates, it is also possible to simplify fixing jigs.

LC3W cross-sectional photograph

LC3W cross-sectional photograph

Fiber Laser Application Lab (Furukawa Electric Chiba Works: Ichihara City, Chiba Prefecture)

The Lab has installed a range of the latest fiber laser processing equipment, including compact 6 kW multi-mode fiber lasers (with a footprint 50% smaller than current fiber lasers), high-precision six-axis multi-joint robotics, and processing optical systems for high-powered lasers. The Lab will continue work toward solving customers’ problems with beam mode control technology, monitor technologies, and other solutions including this recently developed technology.

About Furukawa Electric Group

Furukawa Electric (TSE; 5801, ISIN; JP3827200001) Group started business in 1884, when its copper-smelting facility and wire manufacturing factory was established. Since then Furukawa Electric has become pioneers in the latest technologies by addressing diverse technological issues. Furukawa Electric has released products in a number of areas, including telecommunications, electronics, automobiles, and construction, with the three types of materials it works with at their core, namely, optics, plastics, and metals. Many of these products have attained the top global market share, and all of its products have contributed to society in numerous business areas. Furukawa Electric reported consolidated revenues of JPY 843.3 billion (approximately USD 7.8B) for the fiscal year ended March 31, 2017.