Juha Kotila

Direct Metal Laser Sintering – New Possibilities in Biomedical Part Manufacturing

Direct Metal Laser Sintering (DMLS) has been utilized for prototype manufacturing of functional metal components for years now. During this period the surface quality, mechanical properties, detail resolution and easiness of the process have been improved to the level suitable for direct production of complex metallic components for various applications. The paper will present the latest DMLS technology utilizing EOSINT M270 laser sintering machine and EOSTYLE support generation software for direct and rapid production of complex shaped metallic components for various purposes. The focus of the presentation will be in rapid manufacturing of customized biomedical implants and surgical devices of the latest stainless steel, titanium and cobalt-chromium-molybdenum alloys. In addition to biomedical applications, other application areas where complex metallic parts with stringent requirements are being needed will be presented.

Dimensionally Accurate Mold Inserts and Metal Components by Direct Metal Laser Sintering

One of the main deficiencies in today‘s rapid tooling techniques is the capability of producing only near net-shape parts. Direct Metal Laser Sintering (DMLS) is a technique that enables the fabrication of true net-shape parts in just a few hours with only minimum postprocessing. The DMLS is a laser-based rapid tooling process developed in Europe by Rapid Product Innovations (formerly Electrolux Rapid Development Finland) and EOS GmbH Germany. Rapid Product Innovations was also the first to implement this technology to functional prototyping by using two proprietary bronze-based powders and a new steel-based powder. The technique enables the fabrication of tailored microstructures from porous matrix to near full density. Thus, functionally gradient structures can be fabricated, i.e. material is sintered to full density only where it is needed. This paper describes the philosophy of fabricating true net-shape mold inserts and metal components, but also concentrates on how to maintain the dimensional accuracy even after the post-processing. The study shows that even +/− 0.05 mm accuracy can be obtained. The results of the study also illustrate the beneficial effects of reduced layer thickness and post-processing on the surface roughness and mechanical properties as well as the suitability of various conventional and non-conventional coatings. With reduced layer thickness, the step-shaped effect of the layers was no longer visible. The surface was even further improved by shot peening and coating. In addition, case studies from injection molding, pressure die-casting and direct metal component fabrication are presented.