Synthesis and Preparation Infrastructure
- Chemistry laboratories
Fully equipped chemistry laboratories (70 m² + 20 m²) with nine fume hoods for wet-chemical synthesis and sample preparation.
- Work under protective atmosphere
Two inert-gas glovebox systems, one dedicated to synthesis and one to high-purity processing and characterisation (laminar flow, integrated AFM).
- Thermal processing
A broad range of laboratory furnaces of various geometries and specifications up to 1600 °C, operating either in air or under defined atmospheres (inert gas: nitrogen or argon, oxygen).
- Tube furnaces up to 1500 °C, horizontal, single- and multi-zone, with gas connection (Thermconcept ROC 85/450/13-3z, three-zone, with connections for inert gas, oxygen and forming gas; Thermconcept ROC 75/450/15; Carbolite MTF 12/38/250 up to 1200 °C)
- Muffle furnaces up to 1400 °C, one of which allows sintering under gas atmosphere (4 × Nabertherm up to 1100 °C; Nabertherm P330 up to 1200 °C)
- High-temperature furnaces up to 1600 °C, including a split-hinge furnace for rapid loading (Carbolite-Gero RE-O 230/3 up to 1600 °C; Nabertherm RSH 50/250/13 up to 1300 °C, split design)
- Crystal growth
Bridgman furnace for single-crystal growth up to 1350 °C under inert gas or oxygen.
- High-pressure synthesis
High-pressure laboratory reactor (autoclave) with process data acquisition (Berghof BR-300 with BTC-3000 logger).
- Powder and sample preparation
Uniaxial and isostatic pressing for the production of green bodies (Various uniaxial Hofer isostatic press 500-0,25).
Milling, separation and polishing (planetary ball mill Retsch PM100CM; polishing machine Struers TegraForce-5; centrifuges Hettich 320 R and Heraeus Labofuge 400e).
- Thin-film and coating techniques
Physical vapour deposition of metals and organic molecules (thermal evaporation source Kurt J. Lesker Spectros 150, 30–1200 °C; sputter coater Cressington 208 HR).
- Field-assisted sintering
In-house developed setups for electric field-assisted and ultra-fast sintering.
- Flash sintering: Electrically up to 1500 V and 6 A. Two sample holders: One within a dilatometer (Netzsch DIL 402 Select Expedis, room temperature to 1600 °C) with in-situ tracking of the densification. Second setup within a split-furance with in-situ infrared imaging (Fluke RSE600) of the sample surface.
- Ultra-fast high-temperature sintering (UHS): Setup for sintering under argon atmosphere with heating rates on the order of 10⁴ K/min and peak temperatures in the range of >2000 °C.
Materials Characterisation
- Structural and phase analysis
X-ray diffraction for phase identification and structure determination on powders and bulk samples (Malvern Panalytical Empyrean; Bruker D2 Phaser).
- Microscopy and imaging
Imaging of morphology and microstructure from the millimetre to the nanometre scale (digital microscope Keyence VHX-7000; field-emission scanning electron microscope Philips XL30; atomic force microscopes Asylum Research MFP-3D and NT-MDT Ntegra). Transmission electron microscopy is available through the university's Interdisciplinary Center for Analytics on the Nanoscale (ICAN).
- Calorimetry
Differential scanning calorimetry and adiabatic calorimetry covering a range from −170 °C to 400 °C (Netzsch DSC 300 Caliris Classic; Linseis Chip-DSC 100 up to 400 °C; in-house adiabatic calorimeter with electrocaloric measurement option, −170 °C to +170 °C).
- Thermophysical properties
Determination of thermal diffusivity, thermal conductivity and thermal expansion up to 1600 °C (laser flash analysis Netzsch LFA 467 HyperFlash; dilatometer Netzsch DIL 402 Select Expedis, room temperature to 1600 °C).
- Density and particle size analysis
Determination of skeletal density and particle size distribution of powders (helium pycnometer Porotec Pycnomatic ATC; laser diffraction particle size analyser Cilas 1064).
Electrical Characterisation
- Dielectric and impedance spectroscopy
Broadband impedance and dielectric spectroscopy for the determination of permittivity (up to 1 MHz), conductivity and relaxation behaviour (Solartron ST 1260 impedance/gain-phase analyser with 1296 dielectric interface; Hewlett-Packard 4192A impedance analyser). The impedance measurement setup is equipped with two in-house built sample holders covering a range from liquid-nitrogen temperature into the high-temperature regime: a low-temperature holder (77 K to 450 K) and a high-temperature holder operated inside a tube furnace (room temperature to 1200 °C by design).
- Ferroelectric and piezoelectric measurement
Acquisition of polarisation and strain hysteresis loops as well as small-signal parameters of ferroelectric and piezoelectric materials (aixACCT TF Analyzer 2000 for piezoelectric, ferroelectric and impedance measurements; TREK PD05034 high-voltage amplifier).
- Direct and indirect electrocaloric measurements
Indirect measurement of the electrocaloric effect is done using the aixACCT TF Analyzer 2000.
Direct measurements are performed through a fully custom-built adiabatic calorimeter.
- Magnetoelectric characterisation
Fully custom-developed setup for measuring the direct magnetoelectric effect under combined magnetic and mechanical bias. Static magnetic field up to 1.5 T, mechanical compressive bias up to 20 kN, AC magnetic field from approximately 30 Hz to 100 kHz.
Mechanical Characterisation
- Quasi-static testing
Tensile, compressive and flexural testing over a wide load range (universal testing machine Shimadzu AG-X plus, 20 kN; hydraulic load frame Walter + Bai, 300 kN).
- Fracture mechanics and high-resolution displacement measurement
Fracture toughness determination with sub-micrometre displacement resolution, supported by fibre-optic interferometry (custom-built sub-micron displacement fracture toughness tester; fibre-optic optical displacement sensing system by Attocube).
Building Materials
- Bitumen and bituminous binders
Testing of deformation, flow and low-temperature behaviour according to the relevant standard procedures (ductilometer 41050, Straßentest OHG; penetrometer, InfraTest Testing Systems; dynamic shear rheometer Anton Paar SmartPave 101; bending beam rheometer, Coesfeld Materialtest).
- Fresh mortar, fresh concrete and hardening behaviour
Rheological characterisation of fresh mineral building materials and monitoring of shrinkage and setting (Viskomat NT, Schleibinger; mobile rheometer eBT-V, Schleibinger; shrinkage cone, Schleibinger; ultrasonic multiplex tester IP-8, Ultratest).
- Sample conditioning
Drying ovens up to 120 °C for standard-compliant sample pretreatment and storage (2 × Memmert, Tmax = 120 °C).
