Publikační činnost Katedry pružnosti a pevnosti / Publications of Department of Mechanics of Materials (339)

Permanent URI for this collectionhttp://hdl.handle.net/10084/76025

Kolekce obsahuje bibliografické záznamy publikační činnosti (článků) akademických pracovníků Katedry pružnosti a pevnosti (339) v časopisech registrovaných ve Web of Science od roku 2003 do roku 2014. Katedra byla zrušena.
Do kolekce jsou zařazeny:
a) publikace, u nichž je v originálních dokumentech jako působiště autora (adresa) uvedena Vysoká škola báňská-Technická univerzita Ostrava (VŠB-TUO),
b) publikace, u nichž v originálních dokumentech není v adrese VŠB-TUO uvedena, ale autoři prokazatelně v době jejich zpracování a uveřejnění působili na VŠB-TUO.

Bibliografické záznamy byly původně vytvořeny v kolekci Publikační činnost akademických pracovníků VŠB-TUO, která sleduje publikování akademických pracovníků od roku 1990.

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Now showing 1 - 6 out of 6 results

Antibacterial activity of kaolinite/nanoTiO(2) composites in relation to irradiation time
(Elsevier, 2014) Dědková, Kateřina; Matějová, Kateřina; Lang, Jaroslav; Peikertová, Pavlína; Mamulová Kutláková, Kateřina; Neuwirthová, Lucie; Frydrýšek, Karel; Kukutschová, Jana
The paper addresses laboratory preparation and antibacterial activity testing of kaolinite/nanoTiO2 composite in respect of the daylight irradiation time. Kaolinite/nanoTiO2 composites with 20 and 40 wt% of TiO2 were laboratory prepared, dried at 105 °C and calcined at 600 °C. The calcination caused transformation of kaolinite to metakaolinite and origination of the metakaolinite/nanoTiO2 composite. X-ray powder diffraction, Raman and FTIR spectroscopic methods revealed titanium dioxide only in the form of anatase in all evaluated samples (non-calcined and calcined) and also transformation of kaolinite to metakaolinite after the calcination treatment. Scanning electron microscopy was used as a method for characterization of morphology and elemental composition of the studied samples. A standard microdilution test was used to determine the antibacterial activity using four human pathogenic bacterial strains (Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa). A lamp with a wide spectrum bulb simulating daylight was used for induction of photocatalysis. The antibacterial assays found all the KATI samples to have antibacterial potency with different onset of the activity when calcined samples exhibited antibacterial activity earlier than the non-calcined. Significant difference in antibacterial activity of KATI samples for different bacterial strains was not observed.
Stress-strain behaviour simulation of vanadium microalloyed steel with the internal defects during two different heating strategies
(Springer, 2013) Kvíčala, Miroslav; Frydrýšek, Karel; Hendrych, Aleš
This paper is focused on the explanation of a linkage between two different heating strategies and a grow of the internal casting defects, that are already present in continuously cast blooms made from vanadium micro-alloyed Cr-Mo steel. Internal defects initiation and propagation can be associated to unsuitable casting and heating conditions. Small casting voids surrounded by ferrite-bainite network enriched by carbides forming elements produce perfect conditions for crack grow during the bloom straightening, heating in the soaking pit and/or heat treatment. Moreover, we simulated the stress-strain behaviour of continuously cast round bloom during heating in soaking pit using the FEM software. It is shown that optimized heating strategy led to significantly lower rates of the plastic strain as a crucial value for the crack propagation.
Comparison of strain and stress conditions in conventional and ARB rolling processes
(Elsevier, 2012) Kocich, Radim; Macháčková, Adéla; Fojtík, František
The presented paper outlines the procedure and certain results of the experimental analysis of the strain and stress conditions in a billet during flat rolling. The photo-plasticity method of experimental stress analysis was used to solve the concerned problems. This application for evaluating stress and strain conditions allows to determine the directions as well as the differences of the main strains in the deformed material. The obtained data can then be used to deal with the static conditions of equilibrium by applying the shear stress difference method and the successive approximation method. What exists among the specified results is the comparison of experimental source materials obtained under both the conventional rolling process and multi-layer material rolling (the basis of the accumulative roll bonding process). The main attention was focused on the stress and strain conditions in both procedures.
Contact defects initiation in railroad wheels - experience, experiments and modelling
(Elsevier, 2011) Halama, Radim; Fajkoš, Rostislav; Matušek, Petr; Bábková, Petra; Fojtík, František; Václavek, Leo
Main results of comprehensive research of rolling contact defects initiation are presented in this contribution. Description of own experimental study has been preceded by practical experience of a wheelset producer. A line rolling/sliding contact case with creepage of 0.75% was investigated using a unique test machine. The rail disc was made from Class C steel grade while the wheel disc from R7T steel grade. Unlike the standard twin-disc test, the diameter of the rail disc was 2.6 times bigger than the diameter of the wheel disc. Development of contact cracks and accumulation of shear strain for the wheel material R7T during rolling contact loading were namely evaluated. On the basis of test conditions, simulation by FEM was performed. As the result, very good prediction of shear strain accumulation was achieved using the AbdelKarim–Ohno cyclic plasticity model. The proposed computational strategy can be used for fatigue life prediction till initiation of a crack caused by low-cycle fatigue or by ratcheting failure.
Impact of abrasive mass flow rate when penetrating into a material on its vibration
(Sveučilište J.J. Strossmayera u Osijeku. Strojarski fakultet, 2010) Hreha, Pavol; Hloch, Sergej; Valíček, Jan; Monková, Katarína; Monka, Peter; Harničárová, Marta; Fusek, Martin; Konjatić, Pejo
The article deals with the impact of mass flow rate of abrasive in a water jet when penetrating into a material by using the vibration analysis. The vibrations of material were recorded by sensors placed on the experimental material.Values that were studied were amplitude and FFT (Fast FourierTransform) spectrum of signal. The stainless steel AISI309 was used as the experimental material. Data recorded during the cutting process of theAWJ cutting were analysed by the LabVIEWprogramming environment. The paper outlines the course of the recorded data and the FFTspectrum of this signal. Presented here is only a part of the basic research focused on the application of vibrations as a feedback for on-line control of abrasive water jet.
A modification of AbdelKarim-Ohno model for ratcheting simulations
(Sveučilište J.J. Strossmayera u Osijeku. Strojarski fakultet, 2008) Halama, Radim

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