TAILORWELD · TAILORed Energy Distributions for Laser WELDing

Laser beam welding is a high-performance joining process that is rapidly growing; highlighted by the fact that the global market for laser welding equipment has grown 50% since 2004, and was worth €1.1 Billion in 2011. The market is expected to grow a further 6% in 2012, and approximately 50% of revenues are generated from sales to European manufacturers. The large increase in uptake observed since 2004 has primarily been driven by recent developments in solid-state laser technology leading to the commercial availability of fibre-delivered Yb-fibre, Yb:YAG disc and direct diode laser sources, which have resulted in improved capital cost and reduced operating costs. However, despite these cost reductions and potential benefits, the uptake of laser welding technology is still limited, especially amongst SMEs, for three related reasons: complexity, lack of flexibility, and difficulties in using lasers for ‘non-standard’ welds.Most existing laser systems are fitted with either a standard process head or a 2D galvanometer scanner – both of which deliver a ‘standard’ Gaussian or ‘top-hat’ energy distribution to the work piece. However, this relatively simplistic energy distribution is not directly suitable for many applications and significant laser welding expertise is required in order to develop acceptable process parameters. Laser beam welding with a tailored energy distribution produced by a galvanometer beam scanner is possible, but this technology is not economically attractive. Diffractive optical elements are a robust, simple tool and are capable of producing (virtually) unlimited tailored energy distributions.The aim of the TAILOR:WELD project is to develop and demonstrate an innovative laser welding system, that uses simple and robust diffractive optical elements, which will increase the flexibility and simplify the application of laser welding; removing the key barrier to entry for a large number of SME fabricators.