Wyniki wyszukiwania - Biblioteka Nauki

Ten serwis zostanie wyłączony 2025-02-11.

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 4

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Influence of severe plastic deformation by the ECAP method on structure and properties of the P2-04BCh steel

100%

Greger M. , Vodarek V. , Kander L. , Cizek L.

Archives of Materials Science and Engineering

2009

tom Vol. 37, nr 1

13-20

Purpose: Maim aim of this paper is to describe the plastic deformation executed by ECAE of low carbon steel. The ECAE method lead to significant improvement of strength of investigated material. Design/methodology/approach: Experiments were planned and realised an the temperature ranging from room temperature up 280oC. After application of deformation the structure was investigated in dependence on accumulation of deformation and deformation temperature as well as abovementioned final properties. Findings: Accumulated deformation varied from the value 2 to 8. Investigation of structure by electron microscopy was made with use microscope JEOL JEM 2100. Mechanical properties were investigated by tensile test. Statistic evaluation of angular disorientation and of size of grains/sub-grains was also made with use of electron diffraction (EBSD) in combination with scanning electron microscope FEG SEM Philips. Practical implications: The technology ECAE was applied on low carbon steel. It was verification of ECAE application possibility on steel P2-04BCH importantly for following applying on similar kinds of steel, because ECAE deformation influence. Originality/value: The results from his work shall be useful in determining conditions for fabrication of nanocrystalline or sub-microcrystalline steel by the ECAE technology.

Mechanical properties of ultra-fine grain titanium

100%

Greger M. , Widomska M. , Kander L.

Journal of Achievements in Materials and Manufacturing Engineering

2010

tom Vol. 40, nr 1

33-40

Purpose: The main goal of the presented paper was to describe deformation behaviour of the commercial purity titanium during the ECAP method. Attention was paid particularly on reached mechanical properties of above mentioned material. Design/methodology/approach: Design of experiments rested in extrusion at temperature in range from room temperature up to 280°C. The way of approach was planned in investigation of imposed strain accumulation ability. Among used methods for determination of intended aims were tensile tests, TEM, SEM. Findings: Depending on imposed strain (e = 2 up to 8) was found that mechanical properties (namely tensile strength) have increased up to 960 MPa. Research limitations/implications: Developed ECAP process enables controlling morphology of microstructural constituents and workability of commercially pure titanium. Practical implications: Obtained findings may be used in process of preparing materials for medical application such as dental application where is very important factor their sensitivity to strain. Originality/value: Value of paper is mainly in observed findings that can be used in determination of process conditions at submicro or ultra-fine crystalline materials.

Microstructural evolution of severely deformed Ti

100%

Greger M. , Kander L. , Černý M.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

2009

tom z. 95

19-20

Ultrafine grain formation during equal channel angular extrusion in an Al-Mg-Si alloy

100%

Greger M. , Kocich R. , Čížek L. , Kander L.

2006

tom Vol. 15, nr 1-2

181--185

Purpose: The possibility of including a new methods into classical technologies is one of reasons which for writing this paper. Design/methodology/approach: Microstructural development of aluminium alloy 6082 during equal-channel angular pressing (ECAP). Analysis of structure was made by light microscopy and SEM analysis. Findings: This procedure makes it possible to obtain after 4 passes the grain size of approx. 1 μm. In order to obtain an optimum micro-structure it is necessary to apply more passes with turning of the sample between individual passes by 90° about the longitudinal axis. Research limitations/implications: In this process (ECAP) was one of head problems a impossibility of application other shapes material. One of eventuality solving in respect thereof is using DECAP process. Practical implications: Radii of rounding of working edges of extruding channel must correspond to conditions for laminar flow of metal. Originality/value: Aluminium alloy 6082 was used to ECAP process, and found to be that this material can to change substructure structure, mechanical properties, respectively. Achieved quality level of mechanical properties is a function of number of passes as well as used technological route.