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1

Combined Effect of CrB2 Micropowder and VN Nanopowder on the Strength and Wear Re-sistance of Fe‒Cu–Ni–Sn Matrix Diamond Composites

Ratov Boranbay, Mechnik Volodymyr, Rucki Miroslaw, Gevorkyan Edwin, Kilikevicius Arturas, Kolodnitskyi Vasyl, Siemiatkowski Zbigniew, Umirova Gulzada, Chałko Leszek, Józwik Jerzy, Zhanggirkhanova Arailym, Chishkala Vladimir, Korostyshevskyi Dmytro

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 1

23--34

EN

The paper presents research results on the enhancement of diamond composites designed for tools application for mining industry, hard rocks cutting, able to withstand harsh conditions under heavy dynamical loads. In the present study, both CrB2 micropowder and VN nanopowder additives were used in proportions up to 5 wt.% and 6 wt.%, respectively, together with the basic matrix composition of 51 wt.% Fe, 32 wt.% Cu, 9 wt.% Ni, and 8 wt.% Sn. Addition of both components, CrB2 and VN, appeared to be ad-vantageous in proportion of 2 wt.% and 4 wt.%, respectively. This composition exhibited the highest relative density of 0.9968, better than that without additives. Similarly, the highest values of compressive strength Rcm and flexural strength Rbm were reached for the composite with the same percentage of CrB2 and VN. Compared to the composite with no addition of CrB2 and VN, Rcm improved by almost 70%, while Rbm by 81%. Additionally, the abovementioned additives enhanced the ability of the matrix to prevent the diamond reinforcement from being torn out of the composite, which is very important under harsh working conditions of the cutting tools. The presence of CrB2 micropowder and VN nanopowder promoted densification of the matrix and adhesion between the diamond grits and the Fe‒Cu–Ni–Sn matrix.

2

Microstructure and Fatigue Life of the A359 Alloy Reinforced with Al2O3 after Multiple Remelting

Pietrzak K., Klasik A., Maj M., Sobczak J., Wojciechowski A.

Archives of Foundry Engineering

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2018

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Vol. 18, iss. 2

39--44

EN

The multiple direct remelting of composites based on the A359 alloy reinforced with 20% of Al2O3 particles was performed. The results of both gravity casting and squeeze casting were examined in terms of the obtained microstructure and mechanical characteristics. In microstructure examinations, the combinatorial method based on phase quanta theory was used. In mechanical tests, the modified low cycle fatigue method (MLCF) was applied. The effects obtained after both gravity casting and squeeze casting were compared. It was noted that both characteristics were gradually deteriorating up to the tenth remelting. The main cause was the occurrence of shrinkage porosity after the gravity casting. Much better results were obtained applying the squeeze casting process. The results of microstructure examinations and fatigue tests enabled drawing the conclusion that the A359 alloy reinforced with Al2O3 particles can confer a much better fatigue life behavior to the resulting composite than the A359 alloy without the reinforcement. At the same time, comparing these results with the results of the previous own research carried out on the composites based also on the A359 alloy but reinforced in the whole volume with SiC particles, it has been concluded that both types of the composites can be subjected to multiple remelting without any significant deterioration of the structural and mechanical characteristics. The concepts and advantages of using the combinatorial and MLCF methods in materials research were also presented.

3

Corrosion Resistance of Titanium Based Composites Reinforced with in situ TiB Precipitation Phase

Miklaszewski A.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 4

1767--1770

EN

The paper presents the results of corrosion resistance tests carried out on titanium based composites reinforced with different TiB precipitation phase amount, dependent from boron addition in starting powder blends. Precursor powder preparation and processing parameters of conventional powder metallurgical approach influence density and obtained porosity of bulk compacts. The potentiodynamic tests performed in 0.1 M NaCl solution by the technique of linear voltammetry shows visible difference between compared composite structures. Studies have confirmed that the reinforcement phase amount and its morphology influence obtained microstructure and have important effect on the composite corrosion resistance.

4

Metallographic analysis of surface layer after turning with laser-assisted machining of composite A359/20SiCp

Przestacki D., Szymański P.

Kompozyty

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2011

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R. 11, nr 2

102-106

EN

The composite materials of Al/SiC are increasingly used in various industrial fields such as automotive, aerospace. However, making full use of composite materials is possible when effective methods of machining these materials are known. Due to the content of hard particles, these materials are classified to the group of hard to machine materials. One of the effective method to achieve better performance indicators for making machine parts and equipment is hybrid machining, by which, using the existing way of working, improves machinability. This process is achieved by simultaneously feeding extra heat to the cutting zone, for example by using a laser beam. The work reported here focus on analysis the composite microstructures of A359/20SiCp (F3S.20S DurAlcan™) heated by a laser beam and laser-assisted turned. During analysis of the microstructures of the composite material, the influence of the laser beam on the workpiece was determined and liquid, liquid-solid and neutral matrix zones were identified. The sample surfaces after conventional turning and laser-assisted turning were compared. From the surface layers of the composite there a zone of smaller contents of SiC particles during laser beam heating was determined. As the wedge works in the areas of liquid and liquid-solid, a reduction of the cutting forces, tool wear and the machined surface roughness is expected.

PL

Materiały kompozytowe typu Al/SiC znajdują coraz większe zastosowanie w różnych obszarach przemysłu, np. samochodowego, lotniczego. Jednakże pełne wykorzystanie materiałów kompozytowych możliwe jest w sytuacji, gdy znane są efektywne metody obrabiania tych materiałów. Z powodu zawartości twardych cząstek SiC materiały te zaliczane są do grupy trudno skrawalnych. Jednym z efektywnych sposobów uzyskania lepszych wskaźników użytkowych procesu kształtowania elementów maszyn i urządzeń jest obróbka hybrydowa, dzięki której, wykorzystując już istniejący sposób obróbki, osiąga się poprawę skrawalności poprzez jednoczesne doprowadzenie do strefy skrawania dodatkowej energii cieplnej, np. za pomocą wiązki lasera. W pracy zamieszczono analizę mikrostruktury kompozytu A359/20SiCp (F3S.20S DurAlcan™) toczonego ze wspomaganiem laserowym. Analizując mikrostruktury materiału kompozytowego, określono wpływ oddziaływania wiązki lasera na materiał obrabiany i wyznaczono strefę występowania osnowy ciekłej, ciekło-stałej oraz neutralnej. Porównano powierzchnie próbki toczonej zarówno tradycyjnie, jak i ze wspomaganiem laserowym. Wyznaczono z warstwy wierzchniej kompozytu nagrzewanego laserowo strefę o mniejszej liczbie cząstek SiC. Ponieważ ostrze porusza się w obszarach ciekłej i ciekło-stałej osnowy, należy spodziewać się zmniejszenia siły skrawania, zużycia ostrza oraz chropowatości obrobionej powierzchni.

5

The effect of magnesium on the microstructure of AK7-SiCP composites

Braszczyńska K. N.

Krzepnięcie Metali i Stopów

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2000

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R. 2, nr 44

33--38

EN

The article presents the results of the microstructural investigations of aluminium composites reinforced with silicon carbide particles. The addition of magnesium applied to the matrix alloy has enabled durable and adhesive bonds between the components to be obtained. The studies have also revealed the effect of magnesium on the microstructure of the matrix alloy itself, the occurrence of Mg2Si precipitates, and changes in the composition of the eutectics.

PL

Praca przedstawia wyniki badań mikrostrukturalnych kompozytów aluminiowych umacnianych cząstkami węglika krzemu. Zastosowany dodatek magnezu do stopu osnowy pozwolił na uzyskanie trwałych i spójnych połączeń pomiędzy komponentami. Badania ujawniły również wpływ magnezu na mikrostrukturę samego stopu osnowy, powstawanie wydzieleń Mg2Si oraz zmiany w składzie eutektyk.

6

Analiza powierzchni międzyfazowej w kompozytach AlMg5-SiCcząstki

Zyska A., Braszczyński J.

Krzepnięcie Metali i Stopów

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2000

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R. 2, nr 44

365--372

PL

Zaprezentowano opis termodynamiczny układu kompozytowego stop AlMg5-cząstki SiC. Określono równowagowe stężenia składników strukturalnych kompozytów w zakresie temperatur 923-1223 K. Przedstawiono wyniki badań mikrostruktury kompozytów przeprowadzone przy użyciu transmisyjnego mikroskopu elektronowego. W kompozytach umacnianych cząstkami SiC bez warstwy SiO2 ujawniono na granicach międzyfazowych występowanie węglika glinu, natomiast gdy zastosowano warstwę SiO2, w wyniku reakcji z osnową powstał spinel Al2MgO4

EN

The thermodynamic description of AlMg5 alloy matrix composite with SiC particles was presented. The concentration of structural components in thermodynamic equilibrium in temperature range 923-1223 K was calculated. Using the Thermo-Calc programme (licence A-991122) carried out these calculations. The Newton-Raphson iteration method was used for optimisation g function, which is derived by non-linear equations (5) and linear equations (6), and inequalities (7). In calculation algorithm the following input data were used: process parameters (T,P), initial composition of reaction mixture and list of chemical compounds in product with their chemical potentials values. The results of these calculations were presented in Fig.1. [...]