A5079132819- Metal and Thin Film Mechanics
- Microstructure and mechanical properties
- Advanced Materials and Mechanics
- Fatigue and fracture mechanics
- Cellular and Composite Structures
- Hydrogen embrittlement and corrosion behaviors in metals
- Acoustic Wave Resonator Technologies
- High-Temperature Coating Behaviors
- Aluminum Alloys Composites Properties
- Non-Destructive Testing Techniques
- Copper Interconnects and Reliability
- Machine Learning in Materials Science
- Advanced Surface Polishing Techniques
- Additive Manufacturing and 3D Printing Technologies
- Surface Modification and Superhydrophobicity
- Force Microscopy Techniques and Applications
- High-Velocity Impact and Material Behavior
- Electronic Packaging and Soldering Technologies
- Injection Molding Process and Properties
- Polymer composites and self-healing
- Metallurgy and Material Forming
- Adhesion, Friction, and Surface Interactions
- Research Data Management Practices
- Structural Analysis and Optimization
- Advanced Sensor and Energy Harvesting Materials
University of Freiburg
2014-2024
Fraunhofer Institute for Mechanics of Materials
2015-2024
Fraunhofer Institute for High-Speed Dynamics, Ernst-Mach-Institut
2023
Karlsruhe Institute of Technology
2008-2017
Johns Hopkins University
2006-2015
Applied Materials (Germany)
2011
FZI Research Center for Information Technology
2008
Max Planck Institute for Intelligent Systems
2005-2006
Max Planck Society
2005-2006
University of Stuttgart
2005-2006
Dip-in direct-laser-writing (DLW) optical lithography allows fabricating complex three-dimensional microstructures without the height restrictions of regular DLW. Bow-tie elements assembled into mechanical metamaterials with positive/zero/negative Poisson's ratio and sufficient overall size for direct characterization aim at demonstrating new possibilities respect to rationally designed effective materials.
In this work, the mechanical behaviour of millimetre-scale, bulk single crystalline, nanoporous gold at room temperature is reported for first time. Tension and compression tests were performed with a custom-designed test system that accommodates small-scale samples. The absence grain boundaries in specimens allowed measurement inherent strength millimetre-scale tension. elastic modulus values tension found to be significantly lower than measured nanoindentation-based techniques previously...
Abstract Automated, reliable, and objective microstructure inference from micrographs is essential for a comprehensive understanding of process-microstructure-property relations tailored materials development. However, such inference, with the increasing complexity microstructures, requires advanced segmentation methodologies. While deep learning offers new opportunities, an intuition about required data quality/quantity methodological guideline quantification still missing. This, along...
For soft robotics and programmable metamaterials, novel approaches are required enabling the design of highly integrated thermoresponsive actuating systems. In concept presented here, necessary functional component was obtained by polymer syntheses. First, poly(1,10-decylene adipate) diol (PDA) with a number average molecular weight Mn 3290 g·mol−1 synthesized from 1,10-decanediol adipic acid. Afterward, PDA brought to reaction 4,4′-diphenylmethane diisocyanate 1,4-butanediol. The resulting...
Abstract Shape morphing implicates that a specific condition leads to reaction. The material thus transforms from one shape another in predefined manner. In this paper, not only the target but rather evolution of material's as function applied strain is programmed. To rationalize design process, concepts informatics (processing functions, for example, Poisson's ratio (PR) strain: ν = f (ε) and if‐then‐else conditions) will be introduced. Three types behavior presented: (1) achieving by...
Abstract Materials’ microstructures are signatures of their alloying composition and processing history. Automated, quantitative analyses microstructural constituents were lately accomplished through deep learning approaches. However, shortcomings poor data efficiency domain generalizability across sets, inherently conflicting the expenses associated with annotating experts, extensive materials diversity. To tackle both, we propose to apply a sub-class transfer methods called unsupervised...
Hierarchically structuring materials open the door to a wide range of unexpected and uniquely designed properties. This work presents novel mechanical metamaterial unit cell with strain‐dependent solid–solid phase changes resultant from hierarchically structured “mechanisms” built into an auxetic cell, further realization this kind. The interaction structure mechanism allows stable or metastable elastic energy states be reached as result deformation. is principally analog shape memory...
The local prediction of fatigue damage within polycrystals in a high-cycle setting is long-lasting and challenging task. It requires identifying grains tending to accumulate plastic deformation under cyclic loading. We address this task by transcribing ferritic steel microtexture maps from experiments into microstructure graph. Here, constitute graph nodes connected edges whenever share common boundary. Fatigue loading causes some develop slip markings, which can evolve microcracks lead...
Bistable beams with prebuckled sinusoidal shape are prominently constructed into mechanical metamaterial unit cells bi- and multi-stability. While the effects of boundary conditions thickness on their bistability were more studied, few investigations have been focused effect beam shape. We systematically created new geometries by adding a second term varying in amplitudes wavelengths, onto bistable Nonlinear large deformation finite element modeling showed effective tuning forward backward...
Abstract Data‐driven fatigue strength predictions are gaining popularity. Nevertheless, many machine learning models lack trustworthiness due to their limited decision‐making transparency which often hinders practical application. In this investigation, we assess the expressiveness of model‐agnostic explainable AI method known as SHapley Additive exPlanations (SHAP) for data‐driven prediction. Our study demonstrates that SHAP feature sensitivity analysis underpins physical relations from...
Thin films are used in a wide variety of computing and communication applications although their fatigue behavior its dependence on alloying elements not very well known. In this paper, we present an experimental implementation novel high-throughput testing method for metallic thin films. The methodology uses the fact that surface strain amplitude vibrating cantilever decreases linearly from fixed end to free end. Therefore, film attached will experience gradient corresponding stress...
Self-sealing is one of the fascinating functions in nature that enables living material systems to respond immediately damage. A prime plant model Delosperma cooperi, which can rapidly self-seal damaged succulent leaves by systematically deforming until wound closes. Inspired this self-sealing principle, a novel programmable mechanical metamaterial has been developed mimic underlying damage management concept. This able react autonomously changes its physical condition caused an induced To...
Stress-assisted grain growth at room temperature is identified as a plastic deformation mechanism in nanocrystalline thin films. Unique surface relief attributed to the direct application of stress-coupled boundary migration theory. The figure shows false-color SEM image topography and an AFM height profile result stress-assisted growth. A strategy for tailoring mechanical properties nanostructured metals shown.