Praezisionsbearbeitung mit Festkoerperlaser: Fuegen. Teilprojekt: Werkstoffspezifische und verfahrensoptimierende Untersuchungen zum Fuegen von Werkstoffen geringer Schweisseignung mittels Nd:YAG-Laserstrahlung Abschlussbericht

Abstract

Fundamental material-technical and process-optimizing investigations were done on laser welding of AlMg and AlLi alloys, ceramic particle reinforced Al alloys (PR-MMC), and Ni and Co based alloys, using Nd:YAG lasers with differing output powers and modes. The investigations on high temperature resistant heat-treatable Ni based alloys showed good results for Inconel 718 and Inconel X 750. The tendency of Rene 41 to form cracks can be reduced using suitable parameters. The MMC's are difficult to weld, and tend to spatter, even at low power densities. By using fluxing agents and wire filler (e.g. 'Ti-based reaction welding'), or by preheating, welding results can be considerably improved. Pore-free brazing could be achieved with an automatic power or wire soldering agent filler, using a bifocal processing head and a shielding gas chamber. For monitoring of the joining process, selected temperature, absorption and wavelength measuring methods (pyrometer, photo-diodes, thermo-camera) were used. Also, process monitoring using radiation detection through the optical fibre was employed. An on-line imaging system made it possible to obtain clear video images through the bright plasma plume using intense laser diode radiation. (orig.)SIGLEAvailable from TIB Hannover: F97B95+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman