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Steinau an der Straße, Germany

Meier A.,Laboratory for Precision Machining
Precision Engineering | Year: 2015

Diamond machining is a suitable technology for manufacturing of diffractive optics with excellent surface finish. The machining result depends on the workpiece material to a large extent. Many materials are commonly applied in diamond machining. One material of particular interest is nickel silver, which offers a comparably higher hardness than aluminium or copper. Especially for machining of sharp edges this is an advantageous property. However, not all alloys are equally suited for machining. Therefore, this paper investigates the influences of different material properties on process forces, burr and chip formation, and most importantly the surface finish. The machining experiments demonstrate that burr and chip formation are predominantly influenced by the machining strategy. The process forces on the other hand, largely depend on the material composition, which also affects the surface finish, especially local surface defects. It was also found that an increasing surface hardness, which was generated by deep rolling, supports the reduction of plastic deformations of the machined microstructures. © 2015 Elsevier Inc. All rights reserved. Source

Dankwart C.,BIAS Bremen Institute of Applied Beam Technology | Falldorf C.,BIAS Bremen Institute of Applied Beam Technology | Glabe R.,Laboratory for Precision Machining | Meier A.,Laboratory for Precision Machining | And 2 more authors.
Applied Optics | Year: 2010

Recently, the fabrication of computer-generated holograms by diamond face turning with a nanometerstroke fast tool servo (nFTS) has been demonstrated. Existing methods for the design of diamond-turned holograms account for their spiral-shaped surface topology and the fact that only the phase of a wave field can be modulated. Here we present an algorithm enabling the additional consideration of two important fabrication-related properties: the shape of the diamond tool used and the limited control frequency of the nFTS. Our method is based on the generalized projections method and enables the design of holograms for the reconstruction of arbitrary intensity distributions in the far field. Experimental results are presented, demonstrating the advantages of the method. © 2010 Optical Society of America. Source

Brinksmeier E.,Laboratory for Precision Machining | Orlik B.,Institute for Electrical Drives | Groll R.,AM Technology | Brandao C.,Laboratory for Precision Machining | And 2 more authors.
Production Engineering | Year: 2013

Small machine tools and inherent miniaturized components are persistent development topics in scientific research. Miniaturization usually requires not only reproducing existing systems at a smaller scale, but also a complex integration of various functions into one single element. This concept is presented here by means of a miniature spherical grinding module (GrindBall). It combines a specifically developed magnetic bearing with fluid dynamic propulsion, thus enabling novel grinding kinematics and the possibility of integration in small machine tools. In this paper, the requirements of micro-grinding processes are introduced and the manufacture as well as performance of grinding spheres are discussed; the design of the magnetic bearing is presented and its functionality validated in experiments. Finally, results from numerical simulations leading up to the development of the propulsion system as well as its geometric layout are reported. © 2013 German Academic Society for Production Engineering (WGP). Source

Brinksmeier E.,Laboratory for Precision Machining | Riemer O.,Laboratory for Precision Machining | Kirchberg S.,Clausthal University of Technology | Brandao C.,Laboratory for Precision Machining
Production Engineering | Year: 2013

Micro grinding offers the possibility of machining micro structures in hard and brittle materials producing small-scaled parts. Novel micro grinding systems and machines require miniaturized tools and spindles to meet the demands of small or desktop machines providing a small working space. This paper introduces a novel grinding module called 'GrindBall', with highly integrated tool drive and bearing functions as well as a shaft-free, spherical grinding tool for micro machining applications in small-scaled machine tools. One of the challenges within the development of the GrindBall module is the manufacture of spherical grinding tools, which are not commercially available. A promising method to produce such grinding tools, the injection molding of micro particle filled polymers, is demonstrated in this paper. Injection molding and grinding experiments show that such spherical grinding tools meet the main requirements of this novel grinding technique and show significant material removal rates. © 2013 German Academic Society for Production Engineering (WGP). Source

Meier A.,Laboratory for Precision Machining | Riemer O.,Laboratory for Precision Machining | Brinksmeier E.,Laboratory for Precision Machining
International Journal of Automation Technology | Year: 2016

Diamond machining is a flexible process ensuring an excellent workpiece precision. In combination with fast tool servos, which dynamically modulate the depth of cut, diffractive microstructures and holograms can be machined. The complexity and functionality of the structure depends on the flexibility of the machining process. Novel diamond tool geometries with fine rectangular shaped cutting edges and a width below 20 μm extend the machinable structure geometries. This paper presents fundamental cutting experiments using these novel tools with widths of the cutting edge of 10 μm and 20 μm to machine diffractive microstructures with a rectangular shaped profile. Particularly, the influence of the feed on the uniformity of the structure width and on burr formation on the structure edges is investigated. Using these tools together with fast tool servo assisted diamond turning holograms for multiple wavelengths can be machined, forming different intensity patterns in dependence of the wavelength. © 2016, Fuji Technology Press. All rights reserved. Source

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