Up-to-date fibre lasers produce multi-kw radiation with an excellent beam quality. Compared to CO 2 -lasers, fibre lasers have relatively low operational costs and offer a very high flexibility in production due to the beam delivery with process fibres. As a consequence, fibre lasers have attracted more and more attention. On the other hand, their use in industrial applications especially in the automotive industry is still limited to a certain extent and fibre lasers haven't replaced all other laser sources till now as it could be expected.In laser cutting, the small kerf width produced by fibre lasers should be advantageous since the heated volume is smaller compared to CO 2 -lasers. In fact, cutting velocities are usually much higher which is also caused by the higher absorption coefficient of most metals at the wavelength emitted by fibre lasers. Nevertheless, cutting with fibre lasers of some metals -e.g. stainless steels -is restricted to a small thicknesses of approx. 5mm. The reason for this is that the surface roughness of the edges increases dramatically with the thickness of the work piece.Applications of fibre lasers include e.g. remote welding or even remote cutting of a large variety of materials with usually excellent results. Due to the excellent beam quality the aspect ratio of the weld seam in relation to the penetration depth is quite good. In the case of thin sheet metal welding such a small beam waist is beneficial -but with thicker sheet metals it is very often disadvantageous since the preparation of samples is more complicated, costs increase and requirements on clamping devices rise.In this paper, advantages and disadvantages of fibre lasers are discussed briefly. Applications of a 1.5 kW fibre laser are presented and compared to classical laser systems.

During forming processes high deformations rates can lead to cracks and rupture very easily. Especially brittle materials like titanium or magnesium make difficulties in forming. Due to the dependence of the yield strength on temperature, forming at elevated temperatures eases processing of such materials. Since forming takes place only at localized areas of the work piece selective heating is sufficient and advantageous in most cases. Selective Laser heating offers a possibility to heat only the areas of the work piece where strongest deformations are required. For this purpose several laser sources have been tested like CO2, Diode and Nd:YAG Lasers and their advantages and disadvantages in localized heating of the work pieces will be discussed.The work presented here summarizes research activities at the Institute for Forming and High Power Laser Technology, Vienna University of Technology, on laser assisted deep drawing, laser assisted bending, wire drawing and so on during the last decade. Recent developments like roll profiling, incremental forming processes and hydro forming are discussed briefly.

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