Examination of steel surfaces treated by different lasers

The aim of this paper is to discuss the effect of laser surface treatment with different lasers on the wettability between DC01 steel and SAC305 lead-free solder paste. The field of laser technology is in a constant state of further development. The possible applications of lasers, such as in industrial manufacturing processes and tools for material processing through welding, cutting or engraving, are plentiful. A specific laser treatment can modify the surface energy of steel and affect the wetting properties. In this work, the surfaces of steel plates were treated by Nd:YAG and CO2 laser with different laser powers. After the laser surface treatment wetting experiments were performed between the steel plates and lead-free solder paste. The effect of laser treatment on steel surface microstructure was analyzed by optical microscopy. The wettability of solder pastes were measured with different opening time. The experimental results showed that in case of Nd: YAG laser, the wetting contact angles do not change up to 700 W laser power. Moreover, increasing CO2 laser power results increase of the wetting angles.