High power lasers and their applications in production technology have experienced a vivid development during the last decades and now offer improved performance of classical applications in cutting or welding. Processes that are used since a long time have been improved considerably, for instance hardening. More and more new applications have been developed for instance 3D-printing of metals or forming with laser assistance. Therefore, it is important for production engineers to understand the laser technology and explore how it can be used to enhance production speed, quality, and reduce cost.This book treats the basic principles underlying laser technology, long-time-used equipment and processes but also the most recent improvements and applications, then compares it with the competing conventional technologies. Each of these two parts is preceded by tutorials that inform the reader about the physical basis of the respective technologies. In addition, hazards of these technologies and respective protection are treated for both cases. The book concludes with a detailed comparison of competing technologies and lasers to give a prognosis on the future of lasers in manufacturing. It is written in a style that can be read by people without a broad physical basis and avoids the use of derivations and equations but explains all the material in an easily understandable way in simple words.

If in some processes oxygen is used, additional energy is provided at a rate P ch by chemical reactions. The flow of energy per unit time can then be written: (1. 2) From the above it can be made clear that it is the rate of energy fluxes, i. e. 2 intensities [J/ms] that determines into which channel the energy goes and how the interaction zone will be modified in its state (solid, liquid, gaseous) and geometrical shape (plane, dip, deep hole) -in other words which kind of treatment process will be established (hardening, welding, drilling etc. ). In the following, it will be shown that, in fact, it is the intensity of the beam, which together with the interaction time, primarily governs the interaction phenomena. 1. 1. 2 Laser beam properties determining interaction and energy coupling etJeets In order to yield an efficient process, it is necessary to obtain adequate intensity at the workpiece and to couple a fraction of the incident power as high as possible into the material. The beam properties being of importance in this respect are, (Hugel, 1992): 1. the wavelength A. , governing, in principle, the focusability and absorptivity; 2. the polarisation, having considerable influence on the absorptivity for large angles of incidence; 3. the power P which together with the achievable spot diameter d L f determines the intensity in the interaction zone; 4.

The European Community regards training as a priority area and has therefore developed a series of programmes in the field of vocational training. This book is the result of a pilot project selected under two of these Community Action Programmes. It was initially selected under the COMETT programme, concerned with the development of continuing vocational training in the European Community. Moreover, it was one of the few selected projects to receive further funding under a second selection in the context of the LEONARDO DA VINCI Action Programme for the implementation of a European Community Vocational Training policy. It is with great pleasure that I present the outcome of this project which embodies one of the fundamental objectives of the LEONARDO DA VINCI Programme - training for new technologies in SMEs, which make a significant contribution to economic development in Europe. - K DRAXLER, Director Directorate General XXII European Commission

The European Community regards training as a priority area and has therefore developed a series of programmes in the field of vocational training. This book is the result of a pilot project selected under two of these Community Action Programmes. It was initially selected under the COMETT programme, concerned with the development of continuing vocational training in the European Community. Moreover, it was one of the few selected projects to receive further funding under a second selection in the context of the LEONARDO DA VINCI Action Programme for the implementation of a European Community Vocational Training policy. It is with great pleasure that I present the outcome of this project which embodies one of the fundamental objectives of the LEONARDO DA VINCI Programme -training for new technologies in SMEs, which make a significant contribution to economic development in Europe. K DRAXLER Director Directorate General XXII European Commission x Acknowledgements The Volume Editor gratefully acknowledges funding by the LEONARDO DA VINCI Programme of the Commission of the European Community and by the Austrian Federal Ministry of Science and Transport whose financial support has made the EuroLaser Academy a reality and has led directly to the generation ofthis handbook. He is also indebted to Director Dr. Klaus Draxler, Head of the LEONARDO DA VINCI Programme, DG XXII of the Commission of the European Community, moreover to Director General Raul Kneucker, Minister's Advisor Helmut Schacher and Mrs. Friederike Pranckl-Kloepfer from the Austrian Federal Ministry of Science and Transport.