In the field (of) materialography/material analysis, other complementary processes, such as in-situ X-ray diffraction, are used in addition to the standard analytical methods of light and electron microscopy. In addition, 3D computed tomography is used, for example, to enable a connected to buildings and facilities as a basis for further classical investigations/analyses using common microscopic processes, procedures. In addition to targeted routine investigations, damage investigations of structure and functional materials are also carried out. Using a suitable combination of analytical methods (light microscopy, SEM, EDX and 3D computed tomography), the structure of a material or complete component can be investigated.
Another core competence of the working group is the development of image analysis software for new fields of application in the field (of) microscopy. Where appropriate, these image analysis methods are also used to solve problems.
A list of important routine examinations is shown below.
Steel components
Investigations/analyses of complete and/or
edge-hardened components
Assessment of hardness structure
Degree of steel purity according to
DIN 50 602 and EN 10 247
Grain size
Layer thicknesses
Cast/wrought alloys
Graphite formation
Cast structure
Grain size
Recrystallization
Cavity analysis VDG P201
High performance ceramics
Evaluation / Processing
Reinforcement phases
Grain size
Inhomogeneities
Microstructural defects
Fractography
Project examples
Software development for material microscopy
Software development for material microscopy
Background:
A new depth in the field (of) quantitative microstructure analysis is required in materials analysis. Developments in information technology as well as in digital camera technology and microscopy enable new methods and processes up to automated routine testing of microstructure parameters in materials.
Research objectives & areas of application:
Method and software development for automated microstructure analysis
Use of classic reflected light microscopes and scanning electron microscopy as 2D imaging processes, procedures
Alternative applications, e.g. in the pharmaceutical industry and Biotechnology
Poster (2.71 MB)
CT applications
3D computed tomography
Specification v|tome| x s of the company phoenix|x-ray:
2 X-ray tubes (240 kV microfocus and 180 kV nanofocus™)
High-resolution digital detector (1900 x 1500 pixels)
Resolution of up to 1 µm/voxel
Strong phase contrasts
Precise quantitative 3D characterization of difficult-to-pierce construction and functional materials or microcomponents
Extension of the value chain to include reverse engineering and dimensional metrology by integrating CAD, rapid prototyping and FEM simulation
Areas of application CT (7.03 MB)
SensMik ceramic component
FHprofUnt joint project: "Sensory microscopy to improve the reliability and efficient optimization of manufacturing processes of highly stressed powder technology components (SensMik)"
Background:
In order to counter sustained cost pressure, increasing efforts are being made to produce highly stressed components made of high-strength steels (e.g. tip-hardened 100Cr6) and ceramics by powder injection molding (PIM). A major challenge is meeting the reliability requirements: Microstructural defects such as pores and inhomogeneities act as internal defects or weak points that are the starting point for mechanical failure. These microstructural defects must be largely avoided in the manufacturing process and - since they cannot be completely avoided - their effect on the material strength and its scattering must be quantitatively determined. Valid from School of Engineering, the determination of the strength distribution is carried out with great effort by mechanical examination of a few model samples, statistical evaluations and subsequent fractographic analyses.
Project objectives:
The approach pursued in the project aims at the direct determination of strength properties on the basis of microscopically determined, quantitative microstructure parameters such as flaw size and their statistical evaluation on the component. Furthermore, methods are to be developed to assess the formation and development of microstructural defects within the process chain. This will create a basis for the targeted optimization of individual process steps.
The ultimate aim of the project is to develop methods and tools for quantitative microstructure analysis to evaluate the reliability properties of injection-moulded metal and ceramic high-performance materials and to optimize manufacturing processes in a targeted manner.
Poster (2.58 MB)
Time- and temperature-resolved multidimensional X-ray diffraction plot of the heat treatment process to visualize relevant phase transformations of an overhardened 100Cr6 steel
FHprofUnt joint project: "High-temperature X-ray diffraction in real time as a new method for characterizing dynamic phase transformation processes in materials for Energy Management (real-X-diff)"
Background:
X-ray diffraction (XRD) is one of the oldest and most advanced methods for crystalline structure analysis of condensed matter. Until now, such measurements have been very time-consuming and only reflect a static thermodynamic state. Modern detector and furnace technology now allows us to record diffractograms dynamically on a laboratory scale at 0.5s intervals during thermal, chemical or electrochemical treatment. The observation of such highly time-resolved, dynamic phase transformations was previously only possible with synchrotron radiation in a particle accelerator.
The in-situ XRD system at the Department, Institute of Materials Research (IMFAA) at HTW Aalen is the first laboratory system in the world with such thermal and temporal capabilities.
In-situ XRD X-ray diffraction for the elucidation of age-related crystallographic changes of differently aged cathode active materials in lithium-ion batteries
Project goals:
The aim of the project is to find new materials and process technologies for Energy Management and electromobility or to improve the properties of existing ones with the help of improved real-time processes, procedures for X-ray characterization. To this end, the kinetics of dynamic phase transformation processes and the formation of residual stresses as a function of temperature, time and atmosphere are to be fundamentally investigated and understood. A second goal is to further develop and verify this real-time process, procedure. Investigations/analyses on accuracy and resolution will also be carried out in direct comparison with differential thermal analysis (DTA). Energy-dispersive synchrotron radiation analysis will be used as a further reference method. The final goal at the end of project is to develop a reliable and robust experimental setup that enables such real-time experiments in a simple X-ray laboratory, also under industrial application aspects. The diffraction pattern will be determined on a second scale, which will make it possible, for example, to investigate very fast temperature-driven phase transformations (e.g. also for the important construction material steel) under real process conditions.
