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X-ray diffraction studies of rapid cooled Al-V and Al-Fe-V alloys

Shved O., Mudry S., Girzhon V., Smolyakov O.

Journal of Achievements in Materials and Manufacturing Engineering

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2019

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Vol. 96, nr 1

5--11

EN

Purpose: of this paper is to deep and more complete knowledge about the features of phase and structure formation in Al-based alloys with transition metals (TM) Fe and V at rapid cooling from melt. It is known, that nonequilibrium synthesis conditions of such alloys lead to quasicrystalline, amorphous or metastable phases formation, which can significantly improve the physical-chemical properties and first of all the mechanical ones. But understanding of compositional dependences of structure features at formation under nonequilibrium conditions and the correlation of these dependences with physical properties of alloys is far to be clear. Design/methodology/approach: Structure of Al-enriched Al-V, Al-V-Fe rapid cooled alloys was studied by X-ray diffraction method. In order to estimate the influence of structural state of alloy on the mechanical properties the integral microhardness was studied by Vickers method. Findings: Two quasicrystalline icosaedral phases with different cell parameters are revealed in ternary alloys Al100-3xV2xFex (x=2-4). Increasing of transition metal content promotes the formation of phase with higher quasicell parameter embedded in amorphous matrix. With increasing of the transition elements total content from 6 up to 12 at. % the microhardness of alloys increased gradually from 867 to 3050 MPa. Research limitations/implications: Research of nonequilibrium alloys revealed crystalline structure of Al-V alloys and quasicrystalline embedded in amorphous matrix of Al-Fe-V ternary alloys. Obtained results suppose that further structure and physical properties studies of Al-Fe-V alloys will allows to find the conditions to control the producing of materials with desired properties. Practical implications: Using of rapid cooling method for synthesis of Al-enriched Al-Fe-V alloys give an opportunity to produce alloys with significantly improved mechanical properties. Originality/value: Nonequilibrium conditions of cooling allow significantly changes the structure and properties.

2

An attempt to improve the properties of Ti15V3Al3Cr3Sn titanium alloy by applying an innovative method of shaping-injection with rapid cooling

Klimas J., Łukaszewicz A., Szota M.

Archives of Materials Science and Engineering

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2015

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Vol. 76, nr 2

122--128

EN

Purpose: The study attempts to improve the properties of Ti15V3Al3Cr3Sn titanium alloy by applying an innovative method of shaping, injection with rapid cooling. The comparison of structures and properties of Ti15V3Al3Cr3Sn titanium alloy produced by two methods: conventional one by rolling and by injection with rapid cooling has been presented. Design/methodology/approach: Ti15V3Al3Cr3Sn titanium alloy produced by two methods: traditionally used rolling to achieve products in the form of sheets and unconventionally used injection of molten alloy to mold under pressure with rapid cooling. To achieve the objective the following studies have been carried out: observation of the microstructure by the optical and scanning electron microscope, EDS to verify the chemical composition, roughness measurement to examine surface layer geometry and microhardness tests. Findings: : Observations of microstructures have shown that the Ti15V3Al3Cr3Sn titanium alloy produced by overpressure with rapid cooling has the ability to create fine-grained structure in a top layer with a more ductile core. Such a combination of the structure has enabled to obtain better mechanical properties than the samples produced by the conventional method. Hard, durable and smooth surface layer with a ductile core provides the opportunity to use that material in many fields of materials engineering. Originality/value: The paper presents studies of titanium alloy shaped by the unconventional method of injection to achieve much better properties than for alloys obtained by rolling.

3

Krystalizacja stopów Cu-Zn w procesie przyspieszonego chłodzenia

Wierzbicka B.

Przegląd Odlewnictwa

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1999

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Vol. 49, z. 10

384-386

PL

Mosiądze dwuskładnikowe, o zawartościach cynku występujących w mosiądzach odlewniczych MO59 i MO60, poddano procesowi przyspieszonego chłodzenia. Zabieg tem przeprowadzono na stanowisku badawczym służącym do realizacji procesu tzw. "zamrażania", tj. gwałtownego schładzania próbek z różnej temperatury, w tym także ze stanu ciekłego. Na podstawie dokonanej oceny mikrostruktury próbek wykazano, że optymalna zawartość cynku w mosiężnych próbkach szybkochłodzonych waha się w granicach 36-37%. Zmiana zawartości cynku, przekraczająca 1,5%, prowadzi do wyraźnych zmian mikrostruktury tych próbek.

EN

Binary, zinc containing brasses, like the cast MO59 and MO60 alloys, were subjected to the process of rapid cooling. This treatment was carried out at the research stand which served to the realization of the so-called "freezing" process, it means a rapid cooling of test pieces from various temperature and also from the liquid state. On the basis of the evaluation of the test pieces microstructure it was shown that the best content of zinc in the brass test pieces which were quickly cooled, was in the range of 36-37%. The range of the zinc content which surpassed 1,5% led to considerable changes in microstructure of these test pieces.