LASER MICRO MELTING

摘要

Additive manufacturing (AM) offers a quick and efficient method for prototyping and small batch production with a short delivery time or even individual parts. Components of high geometrical complexity can be directly shaped from metals, metalalloys, metal-matrix composites and from ceramic materials. By a suitable choice of the process parameters AM produced components can meet the demanding requirements of the aerospace, automotive and biomedical industries. Laser micro sintering (LMS) as a further development of selective laser sintering uses fine grained powders below 10 μm to produce high accuracy 3D structures (<25 μm) with a low surface roughness (～3 μm). Up to now, sintering of different material was accomplished through laser radiation in a ns-pulse regime. Recent developments regarding the coating mechanism to achieve higher powder density allows the application of high brilliant continuous radiation for a direct laser micro melting of high resolution structures. This paper will present the principle of the process and the state of the art of laser micro sintering, its advances and limitations, views of the products and the newest results of the further development of this technology. The introduced laser micro melting technology opens up a new dimension for the freeform fabrication of miniature and precise parts with application potentialities in a multitude of engineering fields.