Rapid prototyping by consolidating layers with laser beam includes oscillating beam impact zone to improve surface finish

摘要

Solid articles (8) are built up in layers from liquid or powder raw material (4) using irradiation with a steered beam (16), preferably a laser beam. Especially near the edge regions, the beam (16) is controlled so that the impact zone (30) oscillates. The motion includes forward and backward components as the consolidated strip of material is built up in the forward direction. Solid articles (8) are built up in layers from liquid or powder raw material (4) using irradiation with a steered beam (16), preferably a laser beam. Especially near the edge regions, the beam (16) is controlled so that the impact zone (30) oscillates. The motion includes forward and backward components as the consolidated strip of material is built up in the forward direction. The beam (16) is guided so that it repeatedly covers previously consolidated regions. The oscillation can include a transverse component with the backward step being half the distance of the forward motion. The strength of the beam or the speed of motion can be altered during the backward step. The beam is deflected by a mirror (20) steered with a programmable controller (10).