Interaction between laser beam and BaTiO_3 powders in selective laser sintering treatments

摘要

The research work reported in this paper is an investigation of the behavior of barium titanate powders under selective laser irradiation. Our goal is to determine suitable conditions to sinter the powders and form dense layers usable in some electronic components. On that purpose, compacts of microano BaTiO_3 powder mixes are used for a parametric investigation of the laser scans parameters (power, speed, etc.) with a Nd-YVO_4 laser (23 W). The microstructures obtained after laser treatments are evaluated by XRD, SEM and EDS and compared to a reference specimen manufactured in a conventional way. From this work it can be concluded that a high laser beam power is required to obtain a consolidation of the powder grains and the use of a high scan speed avoids the melting. The scanning speed also influences the final crystallographic state of BaTiO_3. Optimal parameters were founded in order to form a dense and homogeneous tetragonal BaTiO_3 surface.