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Microstructure and physical properties of nanocrystalline Fe75B10Si10Cr5 alloy

Baran Dominika, Czyzewska Natalia, Dziuba Szymon, Przenajkowska Julia, Piesiak Mateusz, Hasiak Mariusz

Interdisciplinary Journal of Engineering Sciences

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2019

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Vol. 7, no. 1

17--22

EN

The main of this paper is to study the microstructure and physical properties of the Fe75B10Si10Cr5 in condition after being produced. The sample was prepared as cylindrical rod with a diameter of 3 mm. The rod was produced using the arc melting method with a suction casting option. It was found that produced alloy was nanocrystalline with average grains of about 15 nm. Due to the different cooling rates in the inner and outer part of the rod, variable sizes of dendrites in the material were observed. The presence of the dendrites was also confirmed on the surface by AFM investigations. The average roughness calculated for chosen profile of the examined area was 6 nm and average hardness of the material equals 844 HV. The mechanical properties were determined in respect to the Oliver-Pharr method. Young’s modulus of the Fe75B10Si10Cr5 calculated from load-displacement curve equals 128 GPa. Magnetic properties of the sample were measured by the vibrating sample magnetometer. The coercivity was equaled 2.184 kA/m, which is relatively low. It means that the Fe75B10Si10Cr5 alloy is magnetically soft.

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Zastosowanie metody zasysania ciekłego metalu do wytwarzania częściowo skrystalizowanego stopu Ti-Zr-Be-Cr

Nabiałek M., Jeziorski L., Szota M., Jędryka J.

Inżynieria Materiałowa

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2012

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Vol. 33, nr 4

264--266

PL

Stopy tytanu z cyrkonem i berylem (seria Vitreloy) cechuje duża zdolność do zeszklenia (GFA – glass-forming ability). Materiały takie ze względu na wyjątkowe właściwości znalazły szerokie zastosowanie m.in. w elektronice i medycynie. Trwają wciąż badania nad opracowaniem nowych składów chemicznych tych stopów oraz metod ich wytwarzania. W pracy przedstawiono niekonwencjonalną metodę wytwarzania amorficznych i częściowo skrystalizowanych stopów na osnowie Ti. Metoda polega na zassaniu ciekłego metalu do chłodzonej miedzianej formy gdzie następuje jego krzepnięcie. Wytworzono wlewki w postaci prętów o średnicy 2, 3 i 4 mm. Wlewki te oraz wlewki krystaliczne poddano badaniu struktury i mikrostruktury metodami dyfrakcji rentgenowskiej oraz mikroskopii świetlnej i elektronowej. Dla wytworzonych stopów prowadzono porównawcze badania twardości, odporności na ścieranie oraz gęstości. Analiza wyników badań pozwala stwierdzić, że stop wytworzony przez szybkie chłodzenie w miedzianej formie cechuje się lepszymi właściwościami w porównaniu ze stopem wytworzonym konwencjonalnie.

EN

Beryllium doped alloys based on Ti and Zr (Vitreloy series) are materials characterized by high adaptability to vitrification (GFE). Such materials usually have unique properties and find many commercial applications. They are used for instance in sports, the electronics industry and medicine. Therefore, ongoing research continues to develop new chemical compositions and methods for their preparation. The paper presents an unconventional method by which it is possible to systematically obtain amorphous and partially crystallized Ti-based materials. This method involves the solidification of liquid metallic material sucked into a chilled copper mould. Samples produced by this method in the form of rods with diameters of 4, 3 and 2 mm and crystal ingots were subjected to examination of their structure and surface using an X-ray diffractometer as well as light and scanning electron microscopy. For all the investigated alloys, comparative tests of mechanical properties such as microhardness, wear resistance and density were made. Surface stereometry was determined for the samples after preliminary melting and solidification. On the basis of the measurements it was found that the materials obtained by rapid solidification cooled in the copper mould exhibit better properties than those produced in the process of natural cooling.

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Właściwości stopów Ti-6Al-4V wytwarzanych konwencjonalnie oraz metodą szybkiego chłodzenia

Jeziorski L., Nabiałek M., Szota M., Frączek T., Jędryka J., Olejnik M.

Inżynieria Materiałowa

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2012

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Vol. 33, nr 3

126--128

PL

W pracy przedstawiono wyniki badań stopów tytanu Ti-6Al-4V wytworzonych metodą konwencjonalną oraz otrzymanych metodą zasysania ciekłego stopu do miedzianej chłodzonej formy. Stopy tytanu charakteryzują się małą gęstością oraz dużą względną wytrzymałością na rozciąganie ( Rm/ρ), także dobrą odpornością na korozję. Są więc materiałami szczególnie atrakcyjnymi dla techniki lotniczej i kosmicznej. Próbki badanego stopu konwencjonalnego oraz wytworzonego w wyniku gwałtownego chłodzenia poddano badaniom struktury i mikrostruktury metodami dyfrakcji rentgenowskiej oraz mikroskopii świetlnej i skaningowej. Określono gęstości tych stopów oraz prowadzono badania morfologii powierzchni i twardości. Analiza porównawcza uzyskanych wyników z wykonanych badań dla stopów Ti-6Al-4V wytworzonych z różnymi prędkościami chłodzenia pozwoliła ustalić wpływ gwałtownej krystalizacji ciekłego metalu na właściwości oraz mikrostrukturę stopów na osnowie tytanu.

EN

The paper presents the comparative results obtained for the alloy Ti-6Al-4V manufactured by the traditional method and by the suction of liquid alloy to a cooled copper mould. It is well known that titanium alloys are characterized by low density and high strength, which makes them very attractive for the aerospace industry. The test samples of the conventional alloy and the alloy produced by rapid cooling were subjected to structure and microstructure examination using the X-ray diffraction method, light microscopy, scanning microscopy and atomic force microscopy. The density of the samples was determined, hardness tests and surface morphology examination were conducted. Comparative analysis of the results of tests performed on the Ti-6Al-4V alloy produced at various cooling rates helped to assess the potential impact of rapid solidification of liquid material on the microstructure and properties of these alloys.

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Arc-plasma spraying and suction-casting methods in magnetic materials manufacturing

Wysłocki J. J., Pawlik P.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 43, nr 1

463--468

EN

Purpose: The paper discusses two new technologies for producing magnetic materials which have been successfully developed in recent years at the Institute of Physics of the Czestochowa University of Technology and discusses properties of the materials obtained with the use of these methods. Design/methodology/approach: In this research the arc-plasma deposition of Nd2Fe14B powders onto a substrate either cooled with water or heated up to a temperature in the range from 773 to1023 K was applied. In the second method the suction of an arc-melted alloy to a water-cooled copper mould (the suction-casting method) was introduced. Moreover, microstructure, magnetic properties and domain structure of the produced samples were determined. Findings: It has been found that thin Nd2Fe14B strips obtained by the plasma method possess magnetic properties. It has also been demonstrated that the suction-casting method makes it possible to obtain both amorphous magnetically soft materials (e.g. Fe-Co-W-Zr-B), as well as magnetically hard nanocomposites (e.g. (Fe-Co)-(Pr-Dy)-B-Zr). Research limitations/implications: The main problem in the suction-casting method is to reduce the critical cooling rate required for the production of amorphous alloys and to increase the geometrical dimensions of amorphous specimens. Practical implications: Thin-layered Nd-Fe-B magnets produced by means of arc-plasma deposition can be applied directly onto the surface of electromagnetic equipment parts. Magnets with isotropic magnetic properties were obtained by applying layers onto the water-cooled copper substrate. Whereas, anisotropic magnets were obtained as a result of the arc-plasma deposition of powders onto the copper substrate heated up to 873 K. The most advantageous properties were achieved for the microcrystalline structure of a grain size close to the single-domain particle size (approx. 0.3 μm). Moreover, it has been demonstrated that the suction-casting method makes it possible to obtain bulk amorphous alloys of considerable sizes, such as rods of magnetically soft Fe-Co-W-Zr-B alloys of a diameter up to 2 mm, as well as Fe-Co-Pr-Zr-B tubes of a diameter up to 3 mm. It is also possible to produce magnetically hard nanocomposite materials of the (Fe-Co)-(Pr,Dy)-B-Zr type by annealing of metallic glasses. Originality/value: Successfully introduced new methods of magnetic materials manufacturing.