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Suche nach „[Sebastian] [Sitzberger]“ hat 22 Publikationen gefunden
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    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Sebastian Sitzberger, Johannes Liebl, Christian J. Trum, Rolf Rascher

    Concept of a two-part clamping system for lenses in optical metrology

    Proceedings of SPIE 11478 (Seventh European Seminar on Precision Optics Manufacturing [Teisnach]), Bellingham, WA, USA

    2020

    DOI: 10.1117/12.2566547

    Abstract anzeigen

    The developed concept represents a universally applicable clamping system designed to fit in any measuring machine with any measuring principle. The design ensures that, as long as the lens remains clamped, the measurement results are reproducible. Form errors due to tension remain constant across all measuring and processing steps. The version presented in this paper was developed especially for small lenses in the diameter range up to 40 mm. On the one hand, the design allows for fast measurement of loose lenses. On the other hand, the device can also be used for measurement comparisons, since lenses can also be mounted permanently. In the following, the concept and first results of measurement tests are presented.

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    Beitrag (Sammelband oder Tagungsband)

    Armin Reif, Sebastian Sitzberger, Rolf Rascher

    Cutting high-performance materials with ultrasonically modulated cutting speed

    Proceedings of SPIE 11478 (Seventh European Seminar on Precision Optics Manufacturing [Teisnach]), Bellingham, WA, USA

    2020

    DOI: 10.1117/12.2565757

    Abstract anzeigen

    The continuing trend towards lightweight construction and the associated machining rates of up to 95 % lead to an increased use of high-performance materials. The ever growing demands on the strength and quality of components and the associated use of materials which are hard to machine require the further development of new, economical machining techniques. In ultrasonic-assisted machining, an additional high-frequency vibration is superimposed on the conventional machining process. The vibration of the tool is usually excited axially or longitudinally to the workpiece, i.e. vertical to the cutting direction. An additional vibration overlay around the rotation axis (torsional) of the tool is also possible. This generates a vibration overlay in the cutting direction. The vibration initiation causes vibration amplitudes in the range of a few micrometers at the tool cutting edge. This leads in turn to a high-frequency change in the cutting speed or feed rate. Overall, an additional torsional vibration overlap can further reduce cutting forces, increase tool life and improve workpiece quality. In order for a grinding tool to generate a torsional vibration, a special tool was required that had to be designed by simulation. The formation of a torsional vibration was achieved by helical slots in the sonotrode. Depending on the angle of rotation and the length of the slots, a part of the axial vibration is converted into a torsional vibration by an axial excitation of the sonotrode. The aim in designing the slots was to achieve the highest possible vibration amplitude. Following the simulation, the slots were inserted into the tool in the corresponding optimum geometric position. Afterwards, the specially designed grinding tool was validated by machining the brittle-hard glass-ceramic material Zerodur. The first test results with the torsionally vibrating tool are presented in the following.

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    Zeitschriftenartikel

    Armin Reif, P. Rinck, Sebastian Sitzberger, Rolf Rascher, M. Zäh

    Zerspanung von Hochleistungswerkstoffen mit ultrasonisch modulierter Schnittgeschwindigkeit

    ZWF - Zeitschrift für wirtschaftlichen Fabrikbetrieb, vol. 115, no. 3, pp. 2-5

    2020

    DOI: 10.3139/104.112255

    Abstract anzeigen

    Die steigenden Anforderungen an die Festigkeit und die Qualität von Bauteilen und die damit verbundene Verwendung hochfester Materialien erfordert die Weiterentwicklung neuer wirtschaftlicher Zerspanungstechniken. Durch eine werkzeugseitige Schwingungsüberlagerung können bei der Bearbeitung von schwer zerspanbaren Werkstoffen die Zerspankräfte und der Werkzeugverschleiß reduziert sowie die Oberflächenqualität verbessert werden.

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    Patent

    Christian J. Trum, Sebastian Sitzberger

    Akkubetriebene Ultraschall-Handbohrmaschine sowie Verfahren zum Betreiben einer solchen Ultraschall-Handbohrmaschine

    2019

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    Patent

    Sebastian Sitzberger, Christian J. Trum, Michael Benisch

    Ultraschall-Handbohrmaschine und Verfahren zum Betreiben einer Ultraschall-Handbohrmaschine

    2019

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Vortrag

    Sebastian Sitzberger, P. Rinck, A. Gueray, Rolf Rascher

    Ultraschallunterstützte Zerspanung von Advanced Materials

    3. Wissenschaftliches Forum zur ULTRASONIC-Bearbeitung, Jena

    2019

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Vortrag

    Sebastian Sitzberger, Jakob Reitberger, Rolf Rascher

    Clamping system for optical components for adaptation in optical production

    10th HLEM 2019 - High Level Expert Meeting Asphere Metrology on Joint Investigations, Braunschweig

    2019

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    Beitrag (Sammelband oder Tagungsband)

    Sebastian Sitzberger, Johannes Liebl, Jakob Reitberger, Rolf Rascher

    Zero-point clamping systems in optical production

    Proceedings of SPIE 11171 (Sixth European Seminar on Precision Optics Manufacturing, 1117101 [April 9th-10th 2019, Teisnach]), Bellingham, WA, USA

    2019

    DOI: 10.1117/12.2528774

    Abstract anzeigen

    Zero point clamping systems are an integral part of the manufacturing industry. They have only yet to find their way into the optical industry. This article compares the hydraulic expansion holder, a clamping system currently used in the optical industry with a zero-point clamping system. The achievable accuracies of both systems are compared over several measurement series. In addition, the process capability evaluation is used for the comparison. Finally, the results are summarized to provide every researcher and practitioner with a foundation for assessing whether zero point clamping systems meet the requirements for the use in optical manufacturing.

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    Patent

    Christian J. Trum, Sebastian Sitzberger

    Kühlsystem für eine Ultraschall-Handbohrmaschine, Ultraschall-Handbohrmaschine sowie Verfahren zum Kühlen einer Schwingungserregereinheit einer Ultraschall-Handbohrmaschine

    2018

    DigitalNachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Christian J. Trum, Christian Vogt, O. Fähnle, Sebastian Sitzberger, Rolf Rascher

    First experiences with Filled-Up-Microscopy (FUM) to evaluate the depth of sub-surface damages on ground surfaces

    Proceedings of EOSAM 2018 (European Optical Society Biennial Meeting; October 2018; Delft, The Netherlands): Optical System Design, Tolerancing, and Fabrication

    2018

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    Vortrag

    Christian J. Trum, Sebastian Sitzberger, Rolf Rascher

    Improved performance of CMP processes through targeted adjustment of polishing slurry and polish pad

    SPIE Optical Engineering + Applications 2018, San Diego, CA, USA

    2018

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    Beitrag (Sammelband oder Tagungsband)

    Christian J. Trum, Sebastian Sitzberger, Rolf Rascher

    Improved performance of CMP processes through targeted adjustment of polishing slurry and polish pad

    Proceedings of SPIE Optical Engineering + Applications (19-23 August, 2018; Optical Manufacturing and Testing XII; San Diego, CA, USA), San Diego, United States, vol. 10742

    2018

    ISBN: 978-1-5106-2055-1

    DOI: 10.1117/12.2321031

    Abstract anzeigen

    Chemical-mechanical polishing (CMP) of optical glasses is widespread and forms the basis for many high-precision polishing processes. The pads, slurries and glass materials used in polishing have many different properties. The effects of these properties on the process results are often unknown. The right choice and combination is therefore often a challenge. By means of a plan processing of N-BK7 and SF56 samples by a plan-polishing process, the influence on the process results, material removal rate (MRR), micro roughness and cleanliness caused by slurry and polishing pad is shown. It turns out that the type of polish pad has the biggest impact on the results. The easy-to-process material N-BK7 shows only little influence by the type of slurry used. The more challenging SF56, however, shows significant effects, especially in the area of the resulting micro roughness and the appearance of surface damages like orange peel. Especially the use of Auerpol® PZ500 shows clear advantages here. For a selection of three out of nine polishing pads, the effect of density variation of the slurry was also investigated. Lower particle concentrations lead to lower material removal rates. This applies to both materials. The more sensitive SF56 shows a reduction in micro roughness by the use of a less dense slurry. The correct selection of the polishing pad has a positive effect on the material removal rate and/or the micro roughness in all tested materials. An adaptation of the type and concentration of the slurry is especially important for more sensitive materials and in combination with the right polishing pad. In view of the development towards special materials and small lot sizes, the targeted and correct selection of polishing slurries and pads becomes more and more important. The information required for this purpose on the behavior of the pads and slurries available on the market must therefore first be determined in a targeted manner and clearly presented.

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    Beitrag (Sammelband oder Tagungsband)

    Christian J. Trum, Christian Vogt, Sebastian Sitzberger, Rolf Rascher, O. Fähnle

    Filled-Up-Microscopy (FUM): a non-destructive method for approximating the depth of sub-surface damage on ground surfaces

    Proceedings of SPIE 10829 (Fifth European Seminar on Precision Optics Manufacturing [April 10-11, 2018; Teisnach])

    2018

    ISBN: 978-1-5106-2270-8

    DOI: 10.1117/12.2318576

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    Beitrag (Sammelband oder Tagungsband)

    Sebastian Sitzberger, Christian J. Trum, Rolf Rascher, M. Zaeh

    Workpiece self-weight in precision optics manufacturing: compensation of workpiece deformations by a fluid bearing

    Proceedings of SPIE 10829 (Fifth European Seminar on Precision Optics Manufacturing [April 10-11, 2018; Teisnach])

    2018

    ISBN: 978-1-5106-2270-8

    DOI: 10.1117/12.2318577

    Abstract anzeigen

    The effects, the extent and the importance of workpiece deformations, particularly lenses, caused by the weight of the workpiece itself, were examined in a previous paper1 . The considered deformations are in the single-digit to two-digit nanometer range. The investigation was carried out by FEM calculations. The conclusion of the previous aper was that a full-surface support of a workpiece in the processing of one surface presumably produces the best results. Furthermore, it was found that if the second functional surface is not to be touched in the process, a full contact lens mounting on its circumference is advisable. An alternative method for fixing precision lenses is therefore desirable. This can be accomplished in two steps. As a first step, the lens must be gripped at its periphery so that none of the optically functional surfaces of the lens is compromised. However, the complete circumference has to be fixated gaplessly because a punctual fixation has the disadvantage of deforming the lens surface asymmetrically. As a second step, the freely hanging lens surface should be supported to minimize deformation. An approach had to be found that supports the surface like a solid bearing but at the same time does not touch it. Therefore, the usage of an incompressible fluid as a hydrostatic bearing for full-surface support is pursued. For this purpose, the bottom side of the lens has to be stored on water. The results of the FEM simulation showed that with a fluid bearing the resulting deformations can be drastically reduced in comparison to a freely hanging surface. Furthermore, under the right conditions, a resulting deformation comparable to a full surface solid support can be achieved. The content of this paper is a test series under laboratory conditions for a first validation of the theoretical results. Therefore, a prototype model to test a lens fixation with a fluid bearing was developed and manufactured. The resulting deformations were measured with an interferometer and the effects are discussed.

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    Vortrag

    Sebastian Sitzberger, Christian J. Trum, Rolf Rascher, M. Zaeh

    Workpiece self-weight induced deformation in precision optics manufacturing

    Posterpräsentation

    5. Tag der Forschung, Deggendorf

    2018

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    Beitrag (Sammelband oder Tagungsband)

    Sebastian Sitzberger, Christian J. Trum, Rolf Rascher

    Analysis of the influence of the workpiece self-weight in precision optics manufacturing using FEM simulation

    Proceedings of SPIE 10326 (Fourth European Seminar on Precision Optics Manufacturing, 1032601 [April 4th-5th 2017, Teisnach])

    2017

    DOI: 10.1117/12.2273023

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    Beitrag (Sammelband oder Tagungsband)

    Christian J. Trum, Sebastian Sitzberger, Rolf Rascher

    Advanced method for the characterization of polishing suspensions

    Proceedings of SPIE 10326 (Fourth European Seminar on Precision Optics Manufacturing, 1032601 [April 4th-5th 2017, Teisnach])

    2017

    DOI: 10.1117/12.2272431

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    Beitrag (Sammelband oder Tagungsband)

    P. Rinck, Sebastian Sitzberger, M. Zaeh

    Actuator design for vibration assisted machining of high performance materials with ultrasonically modulated cutting speed

    Proceedings of SPIE 10326 (Fourth European Seminar on Precision Optics Manufacturing, 1032601 [April 4th-5th 2017, Teisnach])

    2017

    DOI: 10.1117/12.2272133