Facilities
X-ray diffraction XRD
GHI has two x-ray machines at its disposal for material analysis. On the one hand a D8 Advance from Bruker and on the other hand an Empyrean 3rd Gen from Malvern PANalytical. The D8 Advance is widely used for qualitative and quantitative standard measurements. Due to the built-in multiple sample carrier, even high sample volumes can be handled in a short time. The Empyrean with its extensive equipment offers the possibility to perform more complex investigations, such as stress and texture analyses as well as PDF analyses. The equipment of both instruments is listed below in more detail.
Bruker Advanced D8
X-ray tube: copper 1.54059 Ångström
Primary optics: Goebel mirror, parallel beam optics
Sample environment: Sample changer, x-y-z-Stage, high-temperature strip chamber HTK2000N
Secondary optics: Standard optics
Detector: LYNXEYE silicon strip detector with very good energy resolution
Empyrean 3rd gen
X-ray tube: copper 1.54059 Ångström, chromium 2.28973 Ångström, silver 0.55941 Ångström
Primary optics: ICore Copper with automated apertures and BBHD mirror, focusing unit for capillary measurement
Sample environment: 5-axis Euler cradle, high-temperature furnace chamber HTK1200N with capillary unit, capillary spinner
Secondary optics: Standard optics, parallel plate collimator
Detector: GaliPIX3D CdTe sensor, scintiilation counter
Field emission scanning electron microscope
The electron microscope (SEM) GeminiSEM 500 from Zeiss allows magnifications of up to 2 million times and a maximum resolution of 0.6 nanometer are possible. It has a large number of different detectors. An Inlens-SE detector (secondary electron), an Inlens-EsB detector (energy selective backscattered), an Everhart-Thornley-SE detector, a VPSE detector (variable pressure secondary electron) and a backscattered electron detector are installed. Besides, an EDX detector (energy dispersive X-ray spectroscopy) for element analyses and an EBSD detector (Electron Backscatter Diffraction) from Oxford for determination of crystallographic orientation are used. The VPSE detector allows non-conductive samples without coating to be viewed with high resolution at low vacuum. Even at low voltage, high resolutions in perfect image quality can be achieved with this instrument.
Special furnaces
At GHI, various melting furnaces are available for the characterization of melting processes of glass batches and ageing processes of ceramic components. Prominently, there is a 10 kg furnace for investiganting the melting and cooling behaviour of larger batches, as well as a hybrid furnace which can be heated with different energy sources like methane, hydrogen or electrical for evaluating melt behaviour and exhaust fumes.
Aero-acoustic levitation
The Institut of Mineral Engineering has a worldwide unique floating melting plant at its disposal, with which the non-contact determination of thermophysical properties of free-floating crystalline or liquid specimens at temperatures up to 3000 degree celsius is possible. It is mainly used to properties of melts such as density, thermal expansion, surface tension, melting and liquidus temperatures from the high temperature range to the severely undercooled state.
Dilatometry
In dilatometry, the change in length of a sample is measured against the temperature. From the curves, conclusions can be drawn about modification changes, chemical reactions, sintering and melting processes. The GHI is equipped with a dilatometer type L70/2170 LINSEIS, with a swivelling furnace, which allows a fast change between oxidizing and reducing atmosphere. Measurements can be done under oxidizing conditions up to 1700 degree celsius and under reducing conditions up to 2400 degree celsius.
High-Temperature Resonance Frequency Damping Analysis
Resonance frequency damping analysis, briefly RFDA, is suitable for determining the elastic properties at elevated temperatures and different atmospheres. A specimen is excited by a light mechanical pulse and then vibrates at one or more of its resonant frequencies. The resulting acoustic signal is recorded and converted into a frequency-dependent signal by a fast Fourier transform. Depending on the selected excitation position, dynamic elastic properties such as modulus of elasticity, shear modulus, Poisson's ratio and damping can be determined together with the decay behaviour of the specimen vibration. The GHI has a RFDA HT1750 test bench IMCE NV, at its disposal for this purpose, which is usually used for investigations up to 1500 degree celsius in normal atmosphere or under argon flushing.