Wyniki wyszukiwania - Biblioteka Nauki

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

Wyszukiwano:
w słowach kluczowych: directional crystallization

Sortuj według:

Ogranicz wyniki do:

On theorientation characteristic in directionally crystallized Al-CuAl2 eustenic alloy

100%

Góral A. , Jura J. , Paul H.

2008

tom Vol. 53, iss. 1

139-143

The paper presents the orientation characteristics of (Al) and CuAl 2 phases in directionally crystallized Al-CuAl 2 eutectic alloy. The orientations of lamellae of the phases with respect to the crystallization direction and the orientation relationship between neighbouring lamellae were determined using the Electron Back Scattering Diffraction (EBSD) technique in a scanning electron microscope with the application of the formalism of quantitative texture analysis. The global texture was analyzed based on the orientation distribution functions (ODFs) calculated from the pole figures measured using X-ray diffraction technique. There were examined samples obtained at various crystallization rates. The orientation measurements were carried out in selected areas in the plane perpendicular to the crystallization direction. Both the morphology and the microtexture of the alloy changed with the crystallization rate.

W pracy przedstawiono charakterystyki orientacji faz (Al) i CuAl2 w kierunkowo krystalizującym stopie eutektycznym Al-CuAl2 . Orientacje płytek faz względem kierunku krystalizacji oraz relacje orientacji pomiędzy sąsiadującymi płytkami określono przy wykorzystaniu techniki dyfrakcji elektronów wstecznie rozproszonych (EBSD) w skaningowym mikroskopie elektronowym przy zastosowaniu fonnalizmów ilościowej analizy tekstur. Figury biegunowe zmierzone techniką dyfrakcji rentgenowskiej umożliwiły wyznaczenie funkcji rozkladu orientacji i charakterystyką tekstury globalnej. Badano próbki otrzymane przy różnych prędkościach krystalizacji. Pomiary orientacji wykonano w wybranych obszarach w płaszczyźnie prostopadłej do kierunku krystalizacji. Zarówno morfologia jak i mikrotekstura stopu zmieniały się wraz z prędkością krystalizacji.

The microstructure of HS 6-5-2 steel in the areas overlapping remelting obtained by the use of GTAW method

84%

Dziedzic A.

2008

tom Vol. 8, iss. 3

47-52

The work presents microstructures of HS 6-5-2 high-speed steel from the areas overlapping remelting. The surface layer of the steel was remelted using the GTAW method. The microstructure photos were taken with LM and SEM microscopes. On microstructure photos there are visible results of heat effect overlapping remelting. The conclusions of the work show that as a result of crystallization in the zone of first remelting a system of crystals is formed which is forced the direction of heat removal from the front of the crystallization through the solid phase. With overlapping the second remelting on the first one, as a result of retreating crystallization on the border of the second and the first remelting the direction of crystals packing changes. Additionally, the heat influence zone of the second remelting changes the structure of the first remelting significantly. Aforementioned factors determine the decrease of the microhardness value of the surface layer within the areas overlapping remelting.

Microhardness changes of surface layer of HS 6-5-2 steel in the areas overlapping remelting obtained with the use of GTAW method

84%

Bylica A. , Dziedzic A.

2008

tom Vol. 8, iss. 3

25-28

The work presents test results of microhardness of surface layer of HS 6-5-2 high-speed steel from areas overlapping remelting. The surface layer of the steel was remelted using the GTAW method. The microhardness was measured using the Vickers method. The work shows that the area, where the heat influence zone of the second remelting overlapping on the first remelting zone is characterizes by the microhardness lower about approx. 200 HV0,065.

Microstructure of remelted zone of HS 6-5-2 high speed steel

67%

Dziedzic A.

2007

tom Vol. 7, iss. 3

43-46

The work presents microstructures of the remelted zone of HS 6-5-2 high-speed steel. Zones of this kind can be created as a result of treating the material with a CO2 laser beam. The laser processing parameters have been chosen in such a way that the surface layer of steel remelted. The microstructures' images were taken using a scanning microscope. The tests focused on both the directional and volumetric crystallization structures. They imply that - depending on the crystallization conditions - in the remelted zone cells, dendritic cells or dendrites may be formed.