A novel approach for machining of cylindrical hard materials and arbitrary shapes is presented. Alumina-toughened zirconia dental implants with complex geometry are manufactured with femtosecond quasi-tangential laser ablation. This rapid prototyping approach for small-scale production decreases the development-time cycle tremendously and trumps conventional approaches. Moreover, a competitive parameter study for radial and tangential ablation with single and multi-pulse is presented. A process achieving an ablation rate of 1 mm 3 min −1 with a surface roughness R a of 0.2 µm is introduced. The meta-stable tetragonal phase of the ceramic persists and is assessed via Raman spectroscopy. The small heat-affected zone is subsequently ablated with a radial laser process step. Hence, high-precision dental implants with a mean error of smaller 5 µm over the complete contour are shown.

Quasi-tangential laser processing, also called laser turning is increasingly applied for various applications. Specifically, its ability to generate complex geometries with small feature sizes at high precision and surface quality in hard, brittle and electrically non-conductive materials. Due to the geometric flexibility, the process is well suited for prototyping in hard-to-machine materials such as ceramics, carbides and super-abrasives. However, the lack of advanced software solutions for this novel process hitherto limited the exploitation of this potential. Here, we discuss a unique computer-aided manufacturing approach for synchronous 7axis laser manufacturing with quasi-tangential strategies. This gives the peerless possibility to process arbitrary geometries, which cannot be manufactured with conventional techniques. A detailed description of the path calculation with derivation and procedures is given. The generated machine code is tested on a 7-axis laser manufacturing setup. Following, a processed cylindrical ceramic specimen with a continuously varying profile along a helical path is presented. The profile is constituted by a rectangular over half-spherical to a triangular groove with defined pitch. This demonstrator provides the validation of this CAM solution. Measurements of the produced specimen show high adherence with the target geometry with an average deviation below 10 µm.

A novel approach for machining of cylindrical hard materials and arbitrary shapes is presented. Alumina-toughened zirconia dental implants with complex geometry are manufactured with femtosecond quasi-tangential laser ablation. This rapid-prototyping approach for small-scale production decreases the development-time cycle tremendously and trumps conventional approaches. Moreover, a competitive parameter study for radial and tangential ablation with single and multi-pulse is presented. A process achieving an ablation rate of 1mm3/min with a surface roughness Ra of 0.2 µm is introduced. The meta-stable tetragonal phase of the ceramic persists and is assessed via Raman spectroscopy. The small heat-affected zone is subsequently ablated with a radial laser process step. Hence, high-precision dental implants with a mean error of smaller 5 µm over the complete contour are shown.

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