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Joining of the AMC Composites Reinforced with Ti3Al Intermetallic Particles by Resistance Butt Welding

Adamiak M., Tomiczek B., Górka J., Czupryński A.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 2A

847--852

EN

The introduction of new reinforcing materials continues to be investigated to improve the final behaviour of AMCs as well as to avoid some drawbacks of using ceramics as reinforcement. The present work investigates the structure, properties and ability of joining aluminium EN-AW 6061 matrix composite materials reinforced with Ti3Al particles by resistance butt welding as well as composite materials produced by mechanical milling, powder metallurgy and hot extrusion techniques. Mechanically milled and extruded composites show finer and better distribution of reinforcement particles, which leads to better mechanical properties of the obtained products. Finer microstructure improves mechanical properties of obtained composites. The hardness increases twice in the case of mechanically milled composites also, a higher reinforcement content results in higher particle dispersion hardening, for 15 wt.% of intermetallics reinforcement concentration composites reach about 400 MPa UTS. Investigation results of joints show that best hardness and tensile properties of joints can be achieved by altering soft conditions of butt welding process e.g. current flow time 1.2 s and current 1400 A. To improve mechanical properties of butt welding joints age hardening techniques can also be used.

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Charakterystyka tworzywa z fazą Ti3AIC2 reakcyjnie spiekanego pod ciśnieniem

Rutkowski P., Stobierski L., Chlubny L., Górny G.

Materiały Ceramiczne

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2009

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T. 61, nr 3

197-200

PL

W niniejszej pracy opisano próbę otrzymywania tworzyw z układu Ti-AI-C-N metodą reakcyjnego spiekania pod ciśnieniem. W tym celu w pierwszym etapie zsyntezowano proszek Ti3AI, a następnie homogenizowano go z węglem w stosunku wagowym odpowiadającym stechiometrii Ti3AIC2. Mieszaninę poddano spiekaniu reakcyjnemu pod ciśnieniem. Na otrzymanym spieku przeprowadzono obserwację mikrostruktury powierzchni wytrawionych chemicznie. Uzyskane tworzywo poddano analizie rozkładu pierwiastków EDS oraz badaniu rentgenograficznemu. W dalszej części pracy przeprowadzono na spieku pomiary twardości, wytrzymałości na zginanie, właściwości sprężystych oraz odporności na kruche pękanie. Prześledzono również drogę propagacji pęknięcia wygenerowanego przez nakłucie powierzchni spieku piramidką Vickersa.

EN

A trial of manufacture of material in the Ti-AI-C-N system was made by using reactive sintering under pressure. For that purpose, Ti3AI was synthesised in the first step. Then it was homogenized with carbon in the weight ratio corresponding to the stoichiometry of Ti3AIC2. The mixture was exposed to reactive sintering under pressure. The microstructural observation of chemically etched surfaces of the sintered material was made. The EDS element distribution and X-ray diffraction measurements were carried out. Further, the sinter was tested for hardness, bending strength, elastic properties and fracture toughness. Cracks were generated by the Vickers indenter on the surface of the sinter to observe a propagation path.

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Microstructure and properties of Ti-45Al-5V intermetallic alloy

Dymek S., Wróbel M., Witczak Z., Blicharski M.

Materials Science Poland

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2009

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Vol. 27, No. 3

865--873

EN

An alloy of the chemical composition Ti-45Al-5V (at. %) was synthesized by mechanical alloying in a Szegvari-type attritor from elemental powders of high purity. The powders were further consolidated by hot isostatic pressing and hot isostatic extrusion. The resulting material was composed of a mixture of TiAl- and Ti3Al-based phases. However, no lamellar microstructure, typical of such alloys, was observed. The alloys exhibited exceptionally high yield strength, together with satisfactory ductility and fracture toughness. The high strength was unequivocally due to grain refinement and the presence of oxide dispersoid.

4

Selected properties of the aluminium alloy base composites reinforced with intermetallic particles

Adamiak M.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 14, nr 1-2

43--47

EN

Purpose: The main aim of this work is to investigate two types of intermetallics TiAl and Ti3Al as reinforcement and their influence on selected properties and microstructure of aluminium matrix composites. Design/methodology/approach: Aluminium matrix composites were produced employing the atomised aluminium alloy AA6061 as metal matrix, when as reinforcement TiAl and Ti3Al intermetallics particles were used. The powders were cold pressed and then hot extruded. To evaluate the effect of mechanical milling two types of ball mills were used: a low energy (horizontal ball mill) and a high energy one (eccentric ball mill). Reinforcement contents for both processes 5, 10, 15 % by weight. To determine hardness Vickers tests were performed. Microstructure observations were made by optical microscopy and scanning electron microscopy SEM. Findings: Based on the examinations carried out one can state that the mechanical milling can produce composites powders with homogenous distribution of reinforcement particles. The mechanically milled and extruded composites show finer and better distribution of reinforcement particles what leads to better mechanical properties of obtained products. Research limitations/implications: In order to evaluate with more detail the possibility of applying these composite materials at practical application, further investigations should be concentrated on the interface reaction of the matrix and reinforcing particles during elevated temperature exposition and their influence on mechanical properties. Practical implications: The composites materials produced by this way have shown significant improvement of the mechanical properties in comparision with matrix materials. Good properties of the composites make them suitable for various technical and industrial applications. Originality/value: It should be stressed that the materials as intermetallic compounds with outstanding mechanical properties and good thermal stability were developed making them a powerful material to be used in this kind of composites as the alternative for the reinforcements usually investigated and utilized to the composites materials production - alumina or silicon carbide.