PL
 |
EN
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 32

Liczba wyników na stronie
first rewind previous Strona / 2 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 2 next fast forward last
1
Vliv rychlosti ochlazování a tepelného zpracování na mechanické vlastnosti hliníkové slitiny AlSi7Mg0,6
Zapletal J., Věchet S., Kohout J.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2007
|
Vol. 321, z. 89
51-52
EN
This article describes the influences of cooling speed and head treatment on the microstructure and mechanical properties of aluminium alloy AlSi7Mg0,6 (trade description – Anticorodal 72). Results of tensile test (strength, yield strength, ductility, etc. ) to both method heat processing (T6 and T 64).
2
Estimation of tolerance bands of S-N curve
Kohout J., Věchet S., Zapletal J.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2007
|
Vol. 321, z. 89
29-30
EN
A precise determination of tolerance bands of S-N curves is very difficult problem; therefore simple approximate constructions of these bands are often used. Castillo et al. suggested sophisticated and at the same time easy procedure for their estimation which, however, is based on a special type of regression function for describing S-N curve. This type of regression function called the Castillo function is suitable only for high-cycle fatigue region close to fatigue limit. The paper focuses on the Kohout and Vechet function with wider usability applied in the Castillo procedure.
3
Únavová životnost izotermicky zušlechtěné
Kohout J., Zapletal J., Vechét S., Obrtlík K.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2006
|
z. 88
219-222
4
Deviations from power law describing temperature shift of S-N curves
Kohout J., Vechét S.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2006
|
z. 88
161-166
5
Content available remote Regresní modely dĕjů při prodmýchávání oceli v licí pánvi
Moravka J., Michalek K., Kohout J.
Prace Instytutu Metalurgii Żelaza
|
2006
|
T. 58, nr 4
73-75
PL
W pracy podano fizyczne i cybernetyczne sposoby poszukiwania modelu aproksymacyjno-regresywnego kadzi odlewniczej w trakcie przedmuchiwania stali gazem obojętnym. Podejście fizyczne umożliwia stworzenie modelu matematycznego procesu w postaci tak zwanej "białej skrzynki", w której podano strukturę i parametry modelu. Podejście cybernetyczne uwzględnia mierzone wejście i wyjście (tak zwana czarna skrzynka), jak również warunki dodatkowe (tak zwana szara skrzynka). Modele te znane są pod nazwą modeli empirycznych. Niniejszy artykuł prezentuje i porównuje cztery modele - model fizyczny oraz trzy modele empiryczne.
EN
The paper describes the physical and cybernetic approach to the task of looking for an appropriate approximation-regression model of the measured standardised concentration of the tracer at a scale physical model of the casting ladle when blasting the steel by inert gas. The physical approach allows assembling an adequate mathematical model of the processes in the shape of a so-called white box, where the structure (and the parameters) of the model are known. The cybernetic approach only draws on the measured inputs and outputs (so-called black box) as well as any additional conditions (so-called grey box) and the structure of the model is chosen according to them. These models are referred to as empirical models. The paper presents and compares four models - a physically adequate one and three empirical ones.
6
Synthesis, Biological, Immunological and Anticancer Properties of a New Brassinosteroid Ligand
Swaczynova J., Sisa M., Hnilickova J., Kohout J.
Polish Journal of Chemistry
|
2006
|
Vol. 80, nr 4
629-635
EN
We have developed polyclonal antibodies against the brassinosteroid, 24-epicastasterone. Antiserum against this substance was produced by immunizing rabbits and mice with 24-epicastasterone O-(carboxymethyl)oxime (24-epiCS-CMO) conjugated with bovine-serum albumin (BSA). The conjugates were prepared by a mixed anhydride procedure. The antibodies obtained were tested in enzyme-linked immunosorbent assay (ELISA) using 24-epiCS-CMO-peroxidase conjugate. The use of the ELISAallowed detection over the range of 0.01 to 500 pmoles. Natural brassinosteroids (BRs) like brassinolide, and 24-epibrassinolide exhibited relatively high cross-reactivities but many other natural BRs were inactive. The 24-epiCS-CMO ligand was also slightly active in second bean internode bioasaay and on cancer cell lines of different histopathological origin.
7
Regression functions for transition curves
Kohout J., Věchet S.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2005
|
z. 86
241-246
8
Vliv polohy zkušebního tělesa v kýlovém bloku na únavové vlastnosti ADI
Hanzlíková K., Věchet S., Kohout J.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2004
|
z. 78
147-152
9
Vliv podmínek válečkování na charakter povrchových vrstev sedla železničních náprav
Kohout J., Matušek P., Strnadel B.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2004
|
z. 78
99-102
10
Únavové vlastnosti izotermicky zušlechtěné litiny s kuličkovým grafitem se strukturou bainitickou
Zapletal J., Věchet S., Kohout J.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2004
|
z. 78
201-206
11
Simple geometrical description of the dependence of steady-state creep rate on temperature and applied stress
Kohout J., Věchet S.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2004
|
z. 78
153-158
12
Content available remote Únavové vlastnosti litiny s kuličkovým grafitem v závislosti na asymetrii zátěžného cyklu
Věchet S., Kohout J., Hanzlíková K.
Archiwum Odlewnictwa
|
2004
|
R. 4, nr 11/2
283--287
CS
V předložené práci jsou uvedeny výsledky výzkumu zaméřeného na vysokocyklové únavové vlastnosti litin s kuličkovým grafitem sbainitickou strukturou matrice. Únavové vlastnosti jsou hodnoceny na základě stanovení Wöhlerových křivek a meze úavy. Zvláštní pzornost je věnována vlivu asymetrie zátěžného cyklu na hodnoty meze únavy. Pro studovaný materiál byl stanoven Smithůdv a Haighův diagram.
13
Optimization in dwell length of adi isothermal transformation
Hanzlíková K., Věchet S., Kohout J.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2003
|
z. 76
157-162
EN
Austempered ductile iron (ADI) is usually obtained by isothermal heat treatment. Owing to its excellent mechanical as well as technological properties, ADI belongs among prospective structural materials. Recently it is applied also to castings for dynamically loaded machine details, e.g. gear and traversing wheels, crankshafts of motor-cars, vans and trucks, swivel pins, rail brakes and pressure pipes in oil industry [1]. Generally said, ADI castings are applied (i) as a substitution of details made of steel (forged pieces, workpieces or weldments), (ii) instead of the castings made of nodular cast iron with lower level of strength properties to increase its loading capacity and/or its service life, (iii) for the details designed specially for ADI application. Microstructure and mechanical properties of ADI can be substantially influenced by the condition of heat treatment. While the austenitization conditions play only marginal role, the conditions of isothermal transformation, i.e. transformation temperature and the dwell at it, influence the resulting structure of ADI and consequently its mechanical properties very substantially [2-6]. Present paper is devoted to the study how the dwell of isothermal transformation in the range of 2 minutes to 9 hours influences the structure as well as the static and fatigue properties of unalloyed ADI transformed at temperature of 380 °C.
14
Walker's approach and its modification in the Haigh diagram construction
Kohout J., Věchet S.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2002
|
z. 75
77-80
15
Vliv asymetrie zátěžného cyklu na únavové vlastnosti litiny s kuličkovým grafitem
Hanzlíková K., Věchet S., Kohout J.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2002
|
z. 75
73-76
16
Fatigue behaviour of ferritic nodular cast iron at various asymmetry of loading cycle
Kohout J., Věchet S.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2001
|
z. 72
89-92
17
Strain and fracture behaviour of austempered ductile iron
Kohout J., Věchet S., Podrábský T.
Zeszyty Naukowe. Mechanika / Akademia Techniczno-Rolnicza w Bydgoszczy
|
2001
|
Z. 50(233)
133-140
EN
Tensile tests of an unalloyed ADI with the matrix created by upper bainite containing from 30 to 35 % of retained austenite were performed in a temperature range -196 to +200 °C. The temperature dependence of true fracture stress, elongation to fracture, and reduction in area is separated into three regions. Unmonotonous temperature dependence of yield points defined by plastic strain from 0.05 to 2 % in the middle region is the evidence of the stress induced phase transformation of retained austenite into martensite before these values of plastic strain are reached.
18
Mechanical and fatigue properties of ADI
Věchet S., Podrábský T., Kohout J.
Zeszyty Naukowe. Mechanika / Akademia Techniczno-Rolnicza w Bydgoszczy
|
2001
|
Z. 50(233)
127-132
EN
The microstructure and mechanical properties of austempered ductile cast iron (ADI) are substantially influenced, above all, by the conditions of isothermal transformation which have extraordinary crucial influence on the resulting composition of the structural mixture of matrix and, as a consequence, on all its mechanical properties. In the present paper the influence of isothermal transformation temperature changing in the range from 380 to 500 °C on the structure, tensile and fatigue properties of unalloyed nodular cast iron is studied. Mechanical tests were supplied by metallographic analysis and quantitative X-ray phase analysis.
19
Influence of tempering on the properties of ADI and Si-steel
Podrábský T., Kohout J., Věchet S.
Zeszyty Naukowe. Mechanika / Akademia Techniczno-Rolnicza w Bydgoszczy
|
2001
|
Z. 50(233)
121-126
EN
The stability of retained austenite in the as-tempered structure of an isothermally heat-treated Si-steel and of several types of low-alloyed nodular cast iron are studied in the paper. Higher tempering temperatures were used to show their relationship with the changes of mechanical properties, especially toughness and ductility. During tempering and the subsequent cooling, retained austenite can transform to carbide and untempered martensite, bainite and carbide or ferrite and carbide. This transformation of the austenite decreases toughness and plastic properties.
20
Influence of loading-cycle asymmetry on the position of low-cycle fatigue curves
Kohout J.
Zeszyty Naukowe. Mechanika / Akademia Techniczno-Rolnicza w Bydgoszczy
|
2001
|
Z. 50(233)
309-316
EN
Increasing values of the parameter of loading-cycle asymmetry cause a shift of fatigue curves towards higher values of fatigue strength, which was quanti-tatively described by Walker in the high-cycle region. The aim of the presented paper consists in deriving the relations describing the shift of fatigue curves also in the low-cycle region where the shift is usually smaller than that in the high-cycle region and all low-cycle fatigue curves for various parameters of cycle asymmetry converge on the one value of ultimate tensile strength. Two new relations are derived and successfully verified in the paper.
first rewind previous Strona / 2 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.