Fibre Laser Technology at TWI Yorkshire
With a power of over 7kW and a wavelength close to that of the Nd-YAG lasers, the Ytterbium fibre laser installed at TWI Yorkshire offers great potential in terms of welding and cutting operations. Couple this with a highly versatile 6-axis robot manipulating the laser delivery head, and this potential becomes an extremely powerful processing tool available for research and production trials.
TWI's fibre laser combines the outputs of a number of low power (200W) units, using proprietary IPG technology, into a 10m long, 200µm diameter, single optical fibre. The output laser power is transmitted into a four-way optical switch maximising the system's flexibility to process industrial components of different sizes and shapes. A number of twenty metre long, 300µm diameter, single optical fibres transmit the laser power from the optical switch to the laser process head.
TWI has already demonstrated successful welding of 12mm thick C-Mn steel plate, T-joint welding of 8mm to 12mm C-Mn steel, and the combination of the fibre laser with a MAG torch in the hybrid welding of pipeline steels.
Fibre lasers offer the advantage on being easily scalable. The basic set-up of the equipment is fairly compact, and increases in power are achieved simply by adding more of the low power units, with no obvious limit to the power, other than money. Today, the output power of a fibre laser far exceeds that available using Nd:YAG laser technology, whilst also offering a better beam quality. In fact, fibre laser power and beam quality are fast approaching, and in certain cases already even exceeding, those of CO 2 lasers. In addition to the power and beam qualities now available, the fibre laser manufacturers claim high reliability and high power conversion efficiency.
For more information about TWI's fibre laser technology, contact robert.scudamore@twi.co.uk, or follow the links below:
- The effect of spot size and laser beam quality on welding performance when using high-power continuous wave solid-state lasers
- Deep penetration welding - the fibre laser way (Bulletin March 2005) Industrial Members Only
- Manufacturing with Lasers - Developments and Opportunities
- Initial performance assessment of Yb fibre laser technology in the power range from 4 to 7kW for welding structural steel (Industrial Members Report No.822 - March 2005) Industrial Members Only