Characterization of monotonic and fatigue properties

Laboratory for materials testing and study of materials systems

Modern testing machines are used for disruptive material testing and characterization. They are of the type used in current research practices and state-of-the-art university education. They enable, for example, the exact calculation of material properties as of the local stability of joint connections. Monotonic isotherm tensile and pressure tests, cyclical tests (fatigue), quasi-static and cyclical bend tests are currently being carried out at ambient temperatures relevant to engineering applications.


Characterization of material properties for metals, polymers and composites as well as multi-metal or hybrid composite materials.

  • Servo hydraulic testing system ZwickRoell HC25
    Maximum load 25 kN for tensile or compression. Cyclic tensile/compression testing or 3-point bending load with 100 Hz test frequency in maximum.
  • Monotonic tensile testing system ZwickRoell Z020
    Maximum test load 20kN. VideoXtens extensometer with 0.15µm optical resolution. Pneumatic specimen grips for time-saving and eccentric testing of joints.
  • Monotonic tensile testing system ZwickRoell Z100
    Maximum test load 100kN. Extensometers. Mechanical specimen grips
  • Thermal chamber ZwickRoell 400x640
    Temperature range -80°C to 250°C. Usable for test systems HC25, Z020 and Z100
  • Universal testing system ZwickRoell ZHU2,5 incl. instrumented hardness testing
    Maximum load 2.5kN. Hardness tests according to Rockwell, Vickers, Brinell and Martens. 3-point bending tests in specially adapted upper test chamber.
  • Pendulum impact tester ZwickRoell Hit50P
    Charpy impact tests with a working capacity of 50J maximum.
  • Ultrasonic fatigue system (VHCF) for tensile/compressive loading.
    Dynamic tensile/compressive stress at 20 kHz. Maximum vibration amplitude up to 50 m. Stress ratio R = -1.
  • Ultrasonic fatigue system (VHCF) for 3-point bending stresses
    Dynamic 3-point bending stress at 20 kHz. Maximum vibration amplitude up to 57 m. Stress ratio R > 0.
  • Face quenching test facility (Jominy test) Latzke
    Cooling device for standardized Jominy specimens and clamping device for hardness testing equipment to investigate hardness curves.

Dynamic materials characterization

Laboratory for testing velocity-dependent material properties.

Split-Hopkinson test methods are used. These enable highly precise tensile and pressure tests at distortion rates between 100 and 5000/s.


Characterization of material specific values for polymers, fiber composites and metals under stress situations that correspond to crash and impact scenarios in the automotive and aviation sectors.

  • Split-Hopkinson Tension Bar
    Length 12 m for tensile tests with test duration of 1.2 ms, strain rate range 300 /s to 5000 /s
  • Direct-Impact Tension Bar
    Length 40 m for tensile tests with test duration of 15 ms, strain rate range from 50 /s to 500 /s
  • Extended Direct-Impact Compression Bar
    For compression tests with test duration of 2 ms, strain rate range 200 /s to 5000 /s
  • High speed camera
    With up to 1 million fps
  • High Speed Infrared Camera
    For temperature measurements up to 100,000 fps


Imaging techniques

Concurrent multi-scale imaging from atomic structures to macroscopic objects.

Ultrasonic, optical or electron-beam methods are used to render objects of varying sizes at high resolution.


Surface measurement of synthesized semiconductor structures, defect analysis, material transitions, manipulation and contact of micro- and nanostructures, material characterization

  • Automated digital microscope Zeiss Smartzoom 5
    up to 1k magnification, equipped with 3-axis specimen stage as well as continuously adjustable swivel arm (-45° to +45° tilting) for 2D and 3D image acquisition, coaxial LED illumination as well as a ring light, stitching function and 3D height texture are possible.
  • Scanning electron microscope Zeiss EVO15
    with energy dispersive X-ray analysis (EDX). Tungsten cathode with max. resolution of up to 3 nm and magnifications up to 1M, mounted on a 5-axis sample stage, sample chamber with diameter 365mm and max. height 275mm, max. sample weight: 2 kg.
  • Interaction of digital and scanning electron microscope using correlative microscopy
    Interaction of digital and scanning electron microscope using correlative microscopy
  • Far-field microscope
    magnification up to 280x on a 3-axis stage, with a working distance of approx. 20 mm, mountable on test equipment for in-situ measurement
  • Thermal imaging camera MICRO-EPSILON TIM640
    with a measurement range between -20 °C and 900 °C at a 32/125 Hz frame-rate, thermal sensitivity from 40 mK to 80 mK, pixel sizes down to 28 µm
  • Thermal imaging camera Telops Fast-IR M2k
    measuring range 0 °C to 150 °C, 1910/90,000 Hz frame rate with a resolution from 64 x 4 pixels to 320 x 256 pixels. 16-bit sensor, pixel size from 30 µm
  • High speed camera Photron Fastcam SA-Z 2100K
    up to 2 million frames per second at a resolution of 128 x 8 pixels, at highest resolution of 1024 x 1024 pixels up to 20,000 frames per second. 12-bit monochrome camera with external trigger function.
  • JPK Nano Wizard 3
    AFM microscope
  • 3D measurement of infrastructure

Semiconductor characterization

Laboratory for the electrical, optical and structural characterization of semiconductor materials.

Specialized spectroscopic methods are used for defect characterization in semiconductors as in different electrical measurement methods with resolutions as high as the femtoampere range for calculating characteristic parameters.


Defect analysis in silicon and composite semiconductors; determination of charge-carrier density, conductivity and mobility on semiconductor layers; measurement of band gaps, of the refractive index and absorption coefficient of transparent semiconductor materials.

  • Mercury Probe and Probe Station
    Electrical contacting of layers and components
  • Network analyzer
    Measurement of transmission characteristics (piezo-acoustic filter, power electronic components)
  • CV|IV measuring station
    Determination of capacity, conductivity and charge carrier density
  • Dark current measurement station
    Temperature-dependent measurement of conductivity; determination of defect activation energies from Arrhenius plot
  • UV|VIS|NIR spectral photometer
    Determination of layer thickness, band gap, refractive index and absorption coefficients
  • Specialized optical measuring setup for measuring the spectral photoconductivity (CPM)
    as well as photothermal deflection spectroscopy (PDS)
  • High-Resolution X-Ray Diffraction (AR-XRD)
    for structural analysis
  • X-Ray Reflectivity (XRR)
    Determination of film thickness, density and film roughness

Semiconductor manufacture

Laboratory for the vacuum-assisted separation of perovskite absorbers.

Inorganic and organic absorber layers of between 100 and 800 nm are separated in an inert atmosphere. By being embedded in wet-chemically applied transport layers, perovskite solar cells are produced at laboratory scale.


By dimensioning the equipment, the infrastructure can be used to scale up the cells. Additionally, vacuum-assisted vapor-deposition processes enable the application of confirmable layers to textured substrates.

  • Lesker Mini Spectros
    Glovebox integrated low temperature evaporation system
  • Laurell Spin Coater
    up to 8 inch diameter
  • Zeiss Microscope Primotech
    500x magnification

Solid state joining techniques lab

Laboratory for the production of ultrasonically welded joints.

Ultrasonic metal welding systems from various manufacturers are applied. The material-specific, adapted device peripheries enable high value, multi-metal composites or age-resistant hybrid transition structures by power ultrasonics.


Ultrasonically welded joints are increasingly used, e.g. in the automotive and aviation sectors, among others. The technology makes it possible to join materials of different types as well as different metals. The advantages are: very short processing times, joining at moderate temperatures well below melting point for metals, no need for any additional materials or additives.

  • Ultrasonic spot welding machine Telsonic MPX-50
    Working frequency: 20 kHz, max. Power: 7200 W, Max. Welding force: 5000 N
  • Ultrasonic torsion welding machine Telsonic TSP3000E
    Working frequency: 20 kHz, max. Power: 6500 W, Max. Welding force: 3000 N
  • Ultrasonic spot welding machine Branson MWX100
    Operating frequency: 40 kHz, max. Power: 800 W.
  • Ultrasonic spot welding system Herrmann Ultraschall HiS Vario B
    Working frequency: 20 kHz, Max. Power: 4800 W, Max. Welding force: 3500 N
  • Ultrasonic spot welding system Herrmann Ultraschall HiS Vario
    Working frequency: 20 kHz, Max. Power: 6200 W, Max. Welding force: 6000 N
  • Ultrasonic welding press Herrmann Ultraschall HiQ Vario
    Working frequency: 20 kHz, Max. Power: 6200 W, Max. Welding force: 2000 N
  • Ultrasonic hand welder Herrmann Ultraschall HSG
    Working frequency: 35 kHz, Max. Power: 1000 W
  • Polytec IPV-100
    Laser Doppler Vibrometer for In-Plane Vibration Measurement
  • Polytec OFV-5000 XTra, CLV-2534
    Laser Doppler Vibrometer for modal and vibration analysis
  • Polytec VibroGo VGO-200
    Portable Laser-Doppler Vibrometer [LDV]