TY - JOUR A1 - Landesberger, Martin A1 - Kedilioglu, Oguz A1 - Wang, Lijiu A1 - Gan, Weimin A1 - Kornmeier, Joana Rebelo A1 - Reitelshöfer, Sebastian A1 - Franke, Jörg A1 - Hofmann, Michael T1 - High-Precision Visual Servoing for the Neutron Diffractometer STRESS-SPEC at MLZ JF - Sensors N2 - With neutron diffraction, the local stress and texture of metallic components can be analyzed non-destructively. For both, highly accurate positioning of the sample is essential, requiring the measurement at the same sample location from different directions. Current sample-positioning systems in neutron diffraction instruments combine XYZ tables and Eulerian cradles to enable the accurate six-degree-of-freedom (6DoF) handling of samples. However, these systems are not flexible enough. The choice of the rotation center and their range of motion are limited. Industrial six-axis robots have the necessary flexibility, but they lack the required absolute accuracy. This paper proposes a visual servoing system consisting of an industrial six-axis robot enhanced with a high-precision multi-camera tracking system. Its goal is to achieve an absolute positioning accuracy of better than 50μm. A digital twin integrates various data sources from the instrument and the sample in order to enable a fully automatic measurement procedure. This system is also highly relevant for other kinds of processes that require the accurate and flexible handling of objects and tools, e.g., robotic surgery or industrial printing on 3D surfaces. UR - https://doi.org/10.3390/s24092703 Y1 - 2024 UR - https://doi.org/10.3390/s24092703 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-47258 SN - 1424-8220 VL - 24 IS - 9 PB - MDPI CY - Basel ER - TY - JOUR A1 - Li, Xiaohu A1 - Hofmann, Michael A1 - Landesberger, Martin A1 - Reiberg, Marius A1 - Zhang, Xiao A1 - Huang, Yuanding A1 - Wang, Lijiu A1 - Werner, Ewald A1 - Gan, Weimin T1 - A Unique Quenching and Deformation Dilatometer for Combined In Situ Neutron Diffraction Analysis of Engineering Materials JF - Advanced Engineering Materials N2 - A modified quenching and deformation dilatometer (TA instruments DIL 805A/D/T) is now in operation at the Heinz Maier‐Leibnitz Zentrum (MLZ, Germany) neutron center. It is customized for running neutron scattering measurements during the temperature/deformation treatment of the sample, in particular neutron diffraction (phase, texture, and lattice strain) and neutron small angle scattering. The bulk length change of dilatometer specimens is successfully combined with in situ neutron diffraction patterns for analyzing dynamic processes in metallic materials. A detailed introduction to the unique dilatometer is given and examples of recent experiments highlight the use of the added insight provided by combining diffraction and dilatometry. UR - https://doi.org/10.1002/adem.202100163 Y1 - 2021 UR - https://doi.org/10.1002/adem.202100163 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-47789 SN - 1527-2648 SN - 1438-1656 VL - 23 IS - 11 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Li, Xiaohu A1 - Wagner, Julia N. A1 - Stark, Andreas A1 - Koos, Robert A1 - Landesberger, Martin A1 - Hofmann, Michael A1 - Fan, Guohua A1 - Gan, Weimin A1 - Petry, Winfried T1 - Carbon Redistribution Process in Austempered Ductile Iron (ADI) During Heat Treatment—APT and Synchrotron Diffraction Study JF - Metals N2 - In-situ synchrotron diffraction and atom probe tomography (APT) have been used to study the carbon diffusion and redistribution process in austempered ductile iron (ADI) during austempering. The process of carbon content change in bainitic ferrite during different austempering temperatures has been determined quantitatively. The transformation in ADI is controlled by decarburization of supersaturated ferrite and carbide precipitation and has been found to be divided into three stages based on a model developed for bainitic steels by Takahashi and Bhadeshia. The formation, morphology and composition of carbides and carbon clusters in ferrite after austempering have been identified unequivocally by APT. Finally, the relationships of carbon content in ferrite, carbon gap values, and austempering temperatures in the ADI alloy were expressed using empirical equations. UR - https://doi.org/10.3390/met9070789 Y1 - 2019 UR - https://doi.org/10.3390/met9070789 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-47775 SN - 2075-4701 VL - 9 IS - 7 PB - MDPI CY - Basel ER - TY - JOUR A1 - Li, Xiaohu A1 - Saal, P. A1 - Gan, Weimin A1 - Landesberger, Martin A1 - Hoelzel, Markus A1 - Hofmann, Michael T1 - Strain Induced Martensitic Transformation in Austempered Ductile Iron (ADI) JF - Journal of Physics: Conference Series N2 - The strain induced martensitic transformation in austempered ductile iron (ADI) has been investigated using high resolution neutron diffraction on samples compressed ex-situ to different plastic strains. In addition bulk texture measurements using neutron diffraction have been performed to calculate the orientation distribution of ferrite and austenite phases for different strain levels. Combing the detailed texture information with neutron diffraction pattern proved to be essential for quantitative phase analysis and extraction of martensite phase fractions. The martensite content induced by strain in ADI depends on austempering temperature and degree of deformation. UR - https://doi.org/10.1088/1742-6596/746/1/012055 Y1 - 2016 UR - https://doi.org/10.1088/1742-6596/746/1/012055 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-47794 SN - 1742-6588 VL - 746 PB - IOP Publishing CY - Bristol ER -