Influence of the spatial intensity distribution on keyhole stability during high power laser welding

• Applicant: Professor Dr.-Ing. Frank Vollertsen
• Subject Area: Production Automation and Assembly Technology
• Term: from 2010 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 186992358

Beams of modern laser beam sources used for deep penetration welding show different spatial intensity distributions in the focal layer. Experimental observations show that using different laser beam sources affect the dynamics of the welding process. Formation of process pores during laser deep penetration with high aspect ratios depends significantly on process dynamics, especially on the keyhole dynamics. It is assumed that also the formation of process pores can be influenced by the spatial laser intensity distribution. Therefore, the aim of the project is to improve the understanding of the correlations between keyhole dynamics and the spatial laser intensity distribution and to describe the correlation in an analytical model. With the help of the analytical model an optimized spatial laser intensity distribution shall be calculated to improve keyhole stability. An optical system shall be built that allows shaping the laser beam to the previously analytically calculated, optimized spatial intensity distribution to minimize process pore formation during laser deep penetration welding with high aspect ratios.

• DFG Programme: Research Grants