A5070137214- Laser Material Processing Techniques
- Advanced Surface Polishing Techniques
- Advanced Measurement and Metrology Techniques
- Advanced machining processes and optimization
- Additive Manufacturing Materials and Processes
- Advanced Machining and Optimization Techniques
- Surface Roughness and Optical Measurements
- Calibration and Measurement Techniques
- Analytical Chemistry and Sensors
- Thermography and Photoacoustic Techniques
- Force Microscopy Techniques and Applications
- Laser-Ablation Synthesis of Nanoparticles
- Public Administration and Political Analysis
- Cell Image Analysis Techniques
- Law and Political Science
- Medical and Health Sciences Research
- Photoacoustic and Ultrasonic Imaging
- Engineering Technology and Methodologies
- Advanced Sensor Technologies Research
- Industrial Vision Systems and Defect Detection
- Advanced Fluorescence Microscopy Techniques
- Optical Coherence Tomography Applications
- Laser-induced spectroscopy and plasma
University of Bremen
2018-2024
Deutsche Telekom (Austria)
2022
Laser chemical machining (LCM) is a method of laser processing based on gentle material removal by means thermal induced dissolution. Since LCM depends predominantly the surface temperature workpiece, process window restricted appearance gas bubbles at higher powers and their associated shielding effect. In order to extend understanding, influence power modulation behavior investigated in present work. The experiments were conducted titanium grade 1 with phosphoric acid. Based response time...
Due to the challenging environment of micro-manufacturing techniques where workpiece is submerged in a fluid, contactless situ capable measurement required for quality control. However, conditions and small specimen dimensions hinder use conventional metrology. Confocal fluorescence microscopy shown enable step height measurements 2.6 mm thick fluid layer with an uncertainty 8.8 μm by fitting model intensity measured signal. To ascertain potential proposed approach, minimal achievable 0.07...
Laser chemical machining, a non-conventional processing method based on thermally activated electrochemical material dissolution, represents promising technology for manufacturing metallic dies micro forming applications. Prior to widespread industrial acceptance the machining quality of laser should be characterized. For this purpose, is compared with milling regarding both dimensional accuracy and surface quality. Therefore, square cavities exhibiting side walls between 100 μm 400 in...
Laser chemical machining represents a promising technology for manufacturing metallic micro parts. It is usually based on the selective thermal activation of electrochemical material dissolution self-passivating metals in an electrolyte environment. Prior to widespread industrial acceptance, its quality needs be classified within subtractive processes and range machinable materials expanded. For this purpose, line square cavities with dimensions ≤300 μm are machined into high speed steel...
Abstract In nitriding furnaces, the result is currently only controlled indirectly via potential based on gas sensors. Detrimental properties such as soft spots, insufficient compound layer thickness or strongly porous zones, which might from reduced surface reactivity, are thus detected post-process. Therefore, in-process measurements of formation promise a real benefit for energy efficiency and process quality enhancement. Photothermal radiometry promising contactless method inspection...
The challenging environment of in situ micro-geometry measurements fluids (e.g. for laser- or electrochemical machining), such as refractive index fluctuations, small dimensions and high surface gradients, hinder many conventional measurement techniques. Confocal microscopy remains most suitable with uncertainties < 1μm, but complex micro-geometries edge slopes > 75° often produce unwanted artifacts. To prevent the formation artifacts, isotropically emitting fluorescence light a fluid layer...
Zusammenfassung Die Fertigungsgeschwindigkeit der chemischen Laserbearbeitung (LCM) ist derzeit begrenzt, um störende Siedeblasen in Prozessflüssigkeit zu vermeiden. Eine Erhöhung erfordert eine Anpassung des Laserstrahls oder Lasereigenschaften. Das derzeitige Verständnis Mechanismen Oberflächenabtrags für gezielte jedoch unzureichend. Für ein besseres Prozessverständnis bzw. präzise Prozessmodellierung sind prozessbegleitende Messungen Oberflächengeometrie, Oberflächentemperatur und...
Investigation of
The manufacturing rate of laser chemical machining (LCM) is currently restricted to avoid disruptive boiling bubbles in the process fluid. An increase necessitates adjustments beam or fluid properties. However, current understanding surface removal mechanisms insufficient achieve a consistent quality under these conditions. For an improved modeling, in-process measurements geometry, temperature and are required. Due complex environment, no suitable measurement technique for geometry exists....
The optical geometry measurement of submerged micro-surfaces in chaotic fluid environments, e.g., for electric discharge machining (EDM) or laser chemical (LCM), is challenging when the specimen features high aspect ratios and steep surface gradients.To avoid reflection-caused artifacts at gradients, fluorescent molecules are added to layer measured using a confocal fluorescence microscope.A model-based signal processing enables robust, indirect layers > 1 mm, since it capable cope with...