Laser Welding of Dissimilar Materials

The aim of this thesis is to investigate parameters influence in the laser welding of dissimilar metals experimenting with steel and copper by implementing reasoned parameters in the weld of samples using an Ytterbium Fiber Laser and afterwards examining the seams through different methods and draw conclusions in order to suggest an optimize procedure for welding these pair of dissimilar metals. Seven pairs of plates of the chosen specific materials clamped in a designed fixation system were welded with the laser according to the selected parameters that were thought the most interesting ones for the research and proceed afterwards to a macro and micro analysis of the seams observing their features using optical microscope and submitting them to a chemical analysis with SEM-EDX measurements. These analysis were used for drawing solid conclusions of which parameters are preferred to obtain a high quality weldement of these pair of metals attending to general requirements and mechanical properties. The results revealed which range of parameter values, implemented laser variants and techniques are beneficial to acquire a good weldement leaving for further researches test experimentally the mechanical properties of the examined samples in order to confirm the deductions exposed in this investigation