6.1 Materials

1_SARPES

Key technologies combining experimental devices and computational capacity:

• The laboratory for spin- and angle-resolved photoemission spectroscopy (SARPES) for the study of the electron properties of technologically relevant materials was built in collaboration with the SPECS company (Berlin). It is unique in its configuration on a European scale.  SARPES is composed of three chambers under ultra-high vacuum. Two preparatory chambers for the preparation of thin films and their structural characterisation. The third is a photoemission and analysis chamber fitted with a UV lamp, X-Ray tube and electron gun for charge compensation. These unique devices is are supplemented by a ferrous-oxide spin detector and the VSPLEED method (own development). Additional machine and software equipment for materials research includes for example XRD, TEM, SEM, an optical laboratory, layer preparation, software for multi-scale molecular dynamics, etc.
• SPRKKR is quantum-mechanical multi-scale software developed for the description of the electron, magnetic and spectroscopic properties of 2D and 3D materials. It is also used to predict the properties of functional materials for sensory applications. A worldwide first is the predicting the properties of non-periodic materials such as alloys. The SPRKKR software package being developed is currently actively used by over 150 users worldwide, most notably from the fields of material research into alloys, magnetism, spectroscopy and spintronics. Relevant here, is the development of SPRKKR code used to predict and understand the electrical, magnetic and structural properties of industrially relevant materials, such as Heusler alloys, high-entropy alloys or steels (used for the interpretation of experiments and to predict material properties or understand the dependencies behind these properties).

2_POLYMER COMPOSITE

The equipment of these laboratories, built on a unique methodology for the preparation of polymer composite systems with specific material properties for targeted application, includes these key technologies:

• Mikrokompaunder MC15 HT – unique laboratory equipment for the experimental preparation of new polymer materials with the ability to precisely control dispersion and distribution of composite system fillers. Parameters: torque 40 Nm, rotational speed 1-500 rpm, maximum operating temperature 450°C, simultaneous and countercurrent mixing using conical screws, extrusion heads with a thickness of 0.2 and 0.4 mm a width of 60 mm, unwinding roll, air knife.
• The ultrafine frictional grinding mill – one of its kind worldwide – is a device for the preparation of next-generation fillers for composite systems. The patented system of nonporous ceramic discs with varying granularity, with adjustable distances between its upper and lower dead centre, allows for the production of ultrafine particles and fibrils in nano sizes. Parameters: output power 3.75 kW, diameter of discs 150 mm, output ~ 50 kg/h.
• Climatic chamber with solar simulation – a device for the testing of accelerated aging of developed polymer and biopolymer composites. Parameters: temperature ranges -20 to 100°C, humidity range 10–80% RH, radiation 2 × 4 kW, radiation intensity 400–1150 W/m², test area 13600 cm².
• Analysers of aerobic and anaerobic biodegradation – the top device worldwide for the assessment of material and composite system biodegradation during various aerobic (industrial composting) and anaerobic (water treatment plants, landfills, biogas plants) conditions. Measurement of the respiratory activity of microorganisms and their degradation characteristics. Expansion of equipment with supplementary devices and test methods developed internally. Aerobic degradation parameters: temperature range 3–70°C, volume of testing vessel 2.7 l, infra CO₂ sensor, electrochemical O₂ sensor. Anaerobic degradation parameters: temperature range 3–70°C, volume of testing vessel 1 l, infrared CO₂ sensor, infrared CH₄ sensor, electrochemical O₂ sensor.

3_POWDER METALLURGY

The powder metallurgy laboratory for the preparation of new materials with unique microstructures and properties includes key devices:

• The high-energy EMAX ball mill is an unprecedented device in Europe, allowing for high-energy milling of each batch and the preparation of fine-grained homogenous mixtures of powders as well as mechanical superalloys. The device has a cooling circuit that reduces excess cool welding, prevents thermal influence of the batch and allows for the preparation of ultrafine-grained to nanocrystalline powders. The high homogeneity of powder products is ensured by two specially shaped vessels and the ability to reach up to 2000 revolutions per minute. Contamination of the milled material can be entirely reduced by choice of appropriate milling vessel material (carbon steel, ZrO₂, etc.) and filling the vessels with a gaseous medium (inert gasses, oxygen, nitrogen and others).
• Plasma sintering (SPS) machine – a single device of its kind in the Czech Republic and one of the few in Europe allowing the sintering of powder materials in the form of tablets of a diameter up to 50 mm in an inert atmosphere or vacuum up to a temperature of 2400 °C with a 100 kN press.  The high variability in settings of the machine allow for the compaction of electrically conductive and non-conductive materials in graphite or WC/Co dies, discharge of any gaseous substances or reactive sintering inside the die.
• Supplementary instrumentation in the area of powder metallurgy includes the RETSCH PM100 ball mill – sample milling, Leybold Heraeus vacuum induction furnace – sintering of samples, etc.

4_STRUCTURAL MATERIALS

Key equipment in the complex facility includes:

• In the area of bulk deformation this is unique in the Czech Republic, a well-integrated plastometric laboratory with a semicontinuous laboratory rod mill. A simulator, whose core is the plastometer Gleeble 3800 and the Hydrawedge II module (basic tests and physical simulations of complex thermomechanical processing). Part of the simulator is the MAXStrain module (achieving extremely large deformations using alternating hot compression of samples in two directions).
• For computer simulations of forming processes, the programs Forge and Simufact Forming are used, internally developed software Energy 4.0 (calculation of activation energy). Further equipment: Machines for rotary forging, induction furnace for heating and heat treatment, vacuum forge, device for the preparation of nanocrystalline ECAP or HPT metal materials, experimental methods, requirements.
• In the area of powder material processing, uniquely in the Czech Republic there is a machine for the isostatic press (processing of powder materials, further compaction, MIM). EMAX high-energy ball mill, jet mill, high-temperature sintering furnace with debinding unit. Link M2800 brake dynamometer. Vacuum induction furnace with casting into water-cooled rotary wheel (strip casting method).
• The thermal analysis laboratory allows for complex thermophysical, thermodynamic and kinetic study of the developed materials and the processes taking place inside them under precisely defined conditions, in solid and liquid phases. A combination of newly developed methodology with sophisticated and appropriate complimentary experimental systems: TG, DTA, “2D” DSC, TG/DTA and TG/DSC, highly-precise “3D” DSC and DROP calorimetry.
• Dilatometry (at the “nano” level) with temperature or pressing forces modulation, TMA, mass spectrometry, LFA, resting droplet method for the study of the surface properties and interactions between materials, viscosimetry and its modification in a broad band of temperatures (-180 to 2000°C) in controlled experimental conditions in solid and liquid phase. Software applications with corresponding databases for thermodynamic and kinetic calculations (temperature of phase transformations, phase diagrams, TTT and CCT diagrams, mechanical and thermophysical properties and much more).

5_INNOVATIVE STEEL M&T

Key devices built on the equipment and knowledge of the experimental forming and metallography laboratories include:

• A device for the incremental oblique rolling of rods and pipes – a unique rolling mill (in part developed internally) for the rolling of intermediate products with a circular cross-section using the technology of oblique rolling using three rolls. The rolling track is equipped with additional modules for temperature control of stock before rolling (inductors, chamber furnace) in order to achieve the perfect temperature during and after rolling (cooling rings, tempering furnace, quenching bath) for subsequent heat treatment of stock. The machine is fitted with a number of sensors allowing for the monitoring of strength, speed and temperature during the entire process. Parameters: Maximum input diameter 30 mm, 12 mm, minimum input length 800 mm, maximum input length when using inductors / chamber furnace 1500 mm / 3000 mm, maximum rolling strength 100 kN, acceptable rotation speed of main drives 300 rpm, acceptable torques of main drives 1500 Nm.
• Material-technological models for use in a thermomechanical simulator have been compiled based on data from actual processes. These models are used for both the optimisation of parameters (for example when producing die forgings or when designing controlled forging cooling systems) as well as for purposes of testing microalloyed steel alternatives to current materials.
• Thermomechanical simulator – a device that allows the physical simulation of thermal and thermomechanical processing. The machine is based on a servo-hydraulic testing machine with the possibility of tensile and compressive deformations that can be controlled using force or a moving piston. The simulator is further equipped with direct high-frequency resistance heating of samples and a system of combined water and pressured-air cooling. Both of these unique systems were developed on site. Part of the cooling system are two replaceable modules for cylindrical and flat experimental samples. Parameters: Capacity 50 kN, piston movement ± 90 mm, maximum heating power 3 kW, working heating frequency 47 – 67 kHz, max. heating speed 200 °C/sec.
• A unique collection of devices for the advanced characterisation and in-situ testing of materials – comprised of two scanning electron microscopes equipped with special stands for in-situ experiments and a nanoindentation system allowing for the local characterisation of mechanical properties up to a temperature of 550°C. Important among this set of devices is the scanning electron microscope with ultra-high resolution (1 nm), equipped with a focused ion beam allowing for the production of miniature samples of sizes at an order of micrometres in select areas and subsequent in-situ mechanical tests, for example with pressure or bending. The ion beam can also be used to carry out 3D mapping of the chemical composition or microstructure. A second scanning electron microscope is equipped with a heat deformation stand for in-situ observation of microstructures during thermal or mechanical stress or a combination of both, to observe the initiation and propagation of cracks, precipitation processes, phase transitions, etc. 

6_MINIATURE SAMPLES

Key technologies:

• Testing device for the testing of miniature samples – Labortech 10kN electromechanical testing machine, MTS 10kN servohydraulic testing machine, MTS Bionix biaxial servohydraulic testing machine with a capacity of 25kN, SiPlan 10kN servohydraulic testing machine, Zwick Z250 with 10kN load cells, a high-temperature furnace and optical deformation sensor, a number of heat furnaces, 3 ARAMIS systems for digital image correlation, 2 Mercury systems for digital image correlation, 2 instrumented hammers with a capacity of 5 and 15J, Imatek drop weight impact tester, a pair of high-speed cameras for deformation measurements, creep stands for carrying out miniature tests of the construction itself, movable spark gap device for the collection of experimental materials from actual components, optical stereo microscopes for the measurement of sample sizes before and after tests.