Tomasz Henryk Czeppe

Prof. Tomasz Henryk Czeppe


Research Focus & Metrics

Academic Career Length

37Years (1990-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2016 in Acta Materialia
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Journal Article
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PCPaweł Czaja
Paweł Czaja
MFMagdalena Fitta
Magdalena Fitta
JPJanusz Przewoźnik
Janusz Przewoźnik
WMWojciech Maziarz
Wojciech Maziarz
JMJerzy Morgiel
Jerzy Morgiel
ECE. Cesari
E. Cesari

21 December 2018 in Metals
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Journal Article
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OKOlga A. Kogtenkova,
Olga A. Kogtenkova,
Boris B StraumalBoris B Straumal
Boris B Straumal
AKAnna Korneva
Anna Korneva
TCTomasz Henryk Czeppe
Tomasz Henryk Czeppe
AWAnna Wierzbicka-Miernik
Anna Wierzbicka-Miernik
PZPaweł Zięba
Paweł Zięba
High-pressure torsion has been used to obtain the ultra-fine grained (UFG) state with a high specific area of grain boundaries (GBs) in Al-Zn, Al-Mg, Cu-Ag, Cu-Co, and Cu-Ni solid solutions with face-centered cubic (fcc) lattices. The UFG samples were heated in a differential scanning calorimeter (DSC). Small endothermic peaks in the DSC curves were observed in the one-phase solid-solution area of the respective phase diagrams, i.e., far away from the bulk solidus and solvus lines. A possible explanation of these endothermic peaks is based on the hypothesis of phase transformations between GB complexions. This hypothesis has been supported by observations with transmission electron microscopy and electron backscattering diffraction. The new lines of GB phase transformations have been constructed in the Al-Zn, Al-Mg, Cu-Ag, Cu-Co, and Cu-Ni bulk phase diagrams.

24 October 2016 in Journal of Materials Engineering and Performance
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TCTomasz Henryk Czeppe
Tomasz Henryk Czeppe
ASAnna Sypien
Anna Sypien
AWAnna Wierzbicka-Miernik
Anna Wierzbicka-Miernik
The article presents investigations of Ti40Cu36Zr10Pd14 bulk metallic glass crystallization process heated with the rates of 10, 60, 100 and 140 K/min. High heating rates experiments were performed in a new type of differential scanning calorimeter equipped with a fast responding thermal sensor. Phase composition and microstructure were studied with x-ray diffraction and transmission electron microscopy. The observed crystallization proceeded in two separate steps. Applied high rates of heating/cooling resulted in the crystallization of only one CuTi phase, replacing typical multi-phase crystallization. The microstructure after crystallization was polycrystalline with some amount of amorphous phase retained. Kinetic parameters were determined with the use of the Kissinger and Friedman iso-conversional analysis and Matusita–Sakka iso-kinetic model. The kinetic analysis supplies results concerning autocatalytically activated mechanism of primary crystallization with decreasing activation energy and small density of quenched-in nuclei, in good agreement with previous structural investigations. The mechanism of secondary crystallization required dense nuclei site, increasing activation energy and large nucleation frequency. The amorphous phase of Ti40Cu36Zr10Pd14 BMG revealed high thermal stability against crystallization. Application of high heating rates in DSC experiments might be useful for the determination of mechanism and kinetic parameters in investigations of metallic glasses crystallization, giving reasonable results.

2 December 2010 in Journal of Phase Equilibria and Diffusion
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BOBogusław Zbigniew Onderka
Bogusław Zbigniew Onderka
ASAnna Sypien
Anna Sypien
AWAnna Wierzbicka-Miernik
Anna Wierzbicka-Miernik
TCTomasz Henryk Czeppe
Tomasz Henryk Czeppe
LZL. A. Zabdyr
L. A. Zabdyr
Two different methods were employed to prepare samples of the ternary intermetallic phase: AlNi2Ti, and of Al0.4Fe0.5Ni0.1, Al0.4Fe0.3Ni0.3, Al0.4Fe0.1Ni0.5 solid solutions, respectively. Alloys were then subjected to heat treatment for homogenization. Phase identification was made by XRD phase analysis and by the SEM BSE technique, and chemical composition was determined using the EDS method. Heat capacity measurements were made within a temperature range from 100 to 600 K using the DSC technique. Results were listed in tables and then fitted to a Kelley equation; an example of C p vs. T curve is given.

1 April 1990 in Journal of the Less Common Metals
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Journal Article
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ASA. Szytuła
A. Szytuła
TCTomasz Henryk Czeppe
Tomasz Henryk Czeppe
JSJ. Stoch
J. Stoch

24 December 2020 in Materials
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Journal Article
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RBRafał Babilas
Rafał Babilas
KMKatarzyna Młynarek-Żak
Katarzyna Młynarek-Żak
WLWojciech Lonski
Wojciech Lonski
DŁDariusz Łukowiec
Dariusz Łukowiec
MKMariola Kadziołka-Gaweł
Mariola Kadziołka-Gaweł
LTLászló Temleitner
László Temleitner
The aim of the work was to characterize the structure of Al65Cu20Fe15 alloy obtained with the use of conventional casting and rapid solidification-melt-spinning technology. Based on the literature data, the possibility of an icosahedral quasicrystalline phase forming in the Al-Cu-Fe was verified. Structure analysis was performed based on the results of X-ray diffraction, neutron diffraction, 57Fe Mössbauer and transmission electron microscopy. Studies using differential scanning calorimetry were carried out to describe the crystallization mechanism. Additionally, electrochemical tests were performed in order to characterize the influence of the structure and cooling rate on the corrosion resistance. On the basis of the structural studies, the formation of a metastable icosahedral phase and partial amorphous state of ribbon structure were demonstrated. The possibility of the formation of icosahedral quasicrystalline phase I-AlCuFe together with the crystalline phases was indicated by X-ray diffraction (XRD), neutron diffraction (ND) patterns, Mössbauer spectroscopy, high-resolution transmission electron microscopy (HRTEM) observations and differential scanning calorimetry (DSC) curves. The beneficial effect of the application of rapid solidification on the corrosive properties was also confirmed.