Petra Prokopčáková

Technical University of Liberec | TUL · Department of Material Science

The effect of boron addition into Fe–28Al–5Si–X (X = -, 2Mo, or 2Ti) on the structure and high-temperature yield stress was investigated. Generally, the alloying of binary Fe3Al-type iron aluminides by silicon significantly improves high-temperature mechanical properties by solid-solution strengthening. On the other hand, the workability and ductil...

The structures of Fe-28Al-15Si-2Mo iron aluminide in as cast state and in three states after heat-treatments were investigated for the verification of secondary phases stability. Short-term (at 1000 °C for 24 h and at 1200 °C for 2 h) as well as long-term (at 800 °C for 100 h) annealing were performed. Molybdenum addition enhances the high-temperat...

The effect of phase composition and morphology on high-temperature strength in the compression of Fe-Al-Si-based iron aluminides manufactured by casting was investigated. The structure and high-temperature strength in the compression of three alloys-Fe28Al5Si, Fe28Al5Si2Mo, and Fe28Al5Si2Ti-were studied. Long-term (at 800 °C for 100 h) annealing wa...

The microstructural evolution in Fe - Al - Ta alloys containing 23 - 31 at.% Al and 1.5 - 2.2 at.% Ta has been studied in the temperature range 650 - 750 8C by annealing for 1, 10, 100 and 1 000 h. The experiments confirm that in this temperature range the precipitation of the stable hexagonal C14 Laves phase is preceded by formation of coherent, m...

Four quinary Fe–Al–Mo–Ti–B and Fe–Al–W–Ti–B alloys based on Fe3Al produced by vacuum induction melting were investigated regarding their microstructure and mechanical properties. The microstructures consist of a Fe3Al matrix with complex borides along grain boundaries. Compared to other Fe3Al-based alloys the present alloys show favourably low duct...

Since the chemistry of geopolymer materials was discovered, many scientists have studied these new materials and investigated all properties of them as they apply to our lives. Geopolymer materials are known as inorganic materials containing mostly silicon (Si) and aluminum (Al), which were synthesized from dehydroxylated kaolinite activated with p...

The iron aluminide containing 45at.% Al, 4at.% C and 1at.% Si (Pyroferal) was considered as a structural material without any possibility of forming. The brittle character of the material is the reason for cleavage, which takes place on the surface or in the whole volume of the casting during forming, even at high temperatures. A special rolling pr...

A fast and cheap method for the analysis of macronutrients (K, P, Mg and Ca) in leaves of crop plants (wheat, poppy, barley and rape) using double pulse laser induced breakdownspectrometry (LIBS) is suggested. A commercially available LIBSspectrometer was calibrated with the aid of authentic plant samples previously analysed by AAS and ICP-OES afte...

A method for the analysis of chromium in wool fabric samples was developed. It is fast and cheap with no sample preparation. This method involved the use of double pulse Laser Induced BreakdownSpectrometry (LIBS) for the wool fabric samples dyed by two types of metal complex dyes (C.I. Acid Orange 173 and C.I. Acid Black 60). A commercially availab...

Studijní program: P2301 Strojní inženýrství Studijní obor: 3911V011 Materiálové inženýrství 30 výt.