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1

Improving Quality of the EN AC-43300 (AlSi9Mg) Alloy Destined for Castings of a Pump Casings

Jarco A., Dudyk M., Płonka S.

Archives of Foundry Engineering

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2015

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Vol. 15, iss. 2 spec.

31--34

EN

Among non-ferrous alloys, the aluminum alloys have found the most widespread applications within foundry industry. Hypoeutectic silumin of the AlSi9Mg grade is commonly used for large, heavy duty machinery castings with complicated shape and high strength. From technical point of view, tendency to creation of coarse structure can be considered as a drawback of such alloy, what can have adverse effect on properties of the alloy. To obtain optimal structure of the castings and to assure improvement of their mechanical properties, the most effective treatment to perform is modification. Quality of performed modification treatment depends on proper dosing of inoculant and maintaining suitable temperature and time of keeping the alloy before pouring. In the paper are presented test results of crystallization course of refined and modified silumin of the EN AC–43300 (AlSi9Mg) grade, used in castings of pump casings. It has been determined an effect of performed processes of refining and modification on the mechanical properties (Rm, A5, HB and KCV), additionally, metallurgical tests of the alloy have been performed. Basing on analysis of obtained results, the most advantageous modification variant, which is suitable for castings of pump casings and complying with requirements of customers, has been selected.

2

Selection of the Manufacturing of Aluminum Casting Alloys with Hypoeutectic Aluminum Silicon Group

Knych T., Uliasz P., Wiecheć J., Paśko J., Jarosz R.

Archives of Foundry Engineering

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2014

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Vol. 14, iss. 1 spec.

103--108

EN

Aluminum alloys are one of the most popular casting materials. Their enormous popularity due to a wide set of desired material properties such as high strength properties, low thermal expansion coefficient, high thermal and electrical conductivity, very good casting properties, including castability. The most common group of cast aluminum alloys are silumins, where the main alloy addition is silicon. Al-Si alloys are mainly used in the transport industry and construction applications. Another area of applications using this group of materials is the electrical and power engineering industry, where the crucial meaning has the correlation of two types of properties: electrical and mechanical. This paper presents the influence of alloying elements on the electrical properties and mechanical properties of materials undergoing heat treatment. Heat treatment include solution heat treatment and next aging or overaging. Electrical properties represents the electrical conductivity tested by eddy current method. Mechanical properties are in turn represented by the results of measurements of Brinell hardness. Tests include three alloys belong to hypoeutectic silumins group with silicon content in the range of 4,5 to 7 wt%. Si.

3

The effect of FSW parameters on the microstructure and properties of 2017A/AlSi9Mg aluminium alloy welds

Mroczka K.

Inżynieria Materiałowa

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2013

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Vol. 34, nr 4

328--331

EN

The paper discusses the microstructure of FSW welds of aluminum alloys, where one of the alloys (2017A) is in the form of sheet while the other one (AlSi9Mg - hypoeutectic silumin) is a cast plate, both with a thickness of 6 mm. FSW welds are made using different parameters of welding and in different welding conditions, including high welding velocity exceeding 1 m/min. The weld, made using the following parameters of welding: rate of rotation of 560 rpm, and linear velocity of 1120 mm/min, was described in detail. The largest particle fragmentation (mainly Si eutectic - in AlSi9Mg alloy) is identiﬁed at the advancing side; relatively moderate fragmentation is identiﬁed within the weld axis, in the upper part of the weld. In the area above the weld nugget, the material is poorly stirred, and as a result, some of the so-called shrinkages (present in the parent material) are not completely healed (kneaded). For the same reasons, the bands of precipitations are observed in the mentioned area. These particles contain Al, Fe, Mn, Si. These bands are formed by fragmentation of the frame structure of the phase, which is present in the parent material of AlSi9Mg alloy. There is no distribution of the particles of the fragmented phase. It conﬁrrns the lack of mixing of the material as well as the occurrence of signiﬁcant plastic deformation. Mechanical properties are determined on the basis of the hardness proﬁle in cross-sections. The are determined for various distances from the weld's face for the welds, which are performed With the parameters 560/1120, also with shift of the welding line in the 2017A alloy. The analysis showed a signiﬁcant decrease in hardness in the heat affected zone, at the advancing side where 2017A aluminum alloy is located. This tendency of hardness is noticeable for both tested welds.

PL

W pracy omówiono mikrostrukturę zgrzein FSW stopów aluminium, z których jeden (2017A) jest w formie blachy, a drugi (AlSi9Mg - silumin podeutektyczny) odlanej płyty. Zgrzeiny FSW wykonano przy różnych parametrach i warunkach zgrzewania, również z dużą prędkością liniową zgrzewania - powyżej 1 m/min. Szczegółowo opisano zgrzeinę wykonaną przy 560 obr./min, 1120 mm/min. Stwierdzono największe rozdrobnienie cząstek (głównie Si stopu AlSi9Mg) po stronie natarcia i relatywnie średnie w osi zgrzeiny, w górnej części. Nad jądrem zgrzeiny materiał jest słabo wymieszany, a niektóre, tzw. rzadzizny, Występujące w materiale rodzimym, nie ulegają całkowitemu zaleczeniu (zagnieceniu) w tym obszarze. Z tych samych powodów we wspomnianym obszarze zgrzeiny są obserwowane pasma cząstek fazy zawierającej Al, Fe, Mn, Si. Pasma te powstały w wyniku fragmentacji fazy o szkieletowej budowie, która jest obecna wmateriale rodzimym stopu AlSi9Mg. Nie doszło jednak do rozprowadzenia cząstek fragmentowanej fazy, co potwierdza tezę o braku wymieszania materiału, ale również o wystąpieniu znacznych odkształceń plastycznych. Właściwości mechaniczne określono na podstawie profili twardości na przekrojach poprzecznych. Profile wyznaczono dla różnych odległości od lica zgrzeiny w zgrzeinach wykonanych przy parametrach 560/1120, z tym, że jedna zgrzeina była wykonana z przesunięciem linii zgrzewania w stronę natarcia (w stop 2017A). Analiza proﬁlu twardości wykazała spadek twardości stopu 2017A w streﬁe wpływu ciepła. Ta tendencja zmian twardości jest widoczna dla obu badanych zgrzein.

4

The Influence of Chemical Composition and Parameters of Heat Treatment on the Mechanical Properties and Electrical Conductivity in Hypoeutectic Aluminium Silicon Alloys

Wiecheć J., Uliasz P., Knych T., Piwowarska-Uliasz M., Jarosz R.

Archives of Foundry Engineering

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2013

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Vol. 13, iss. 3 spec.

179--184

EN

The silumins are the aluminum alloys with the silicon as the main alloy addition. These are one of the most common types of casting alloys based on aluminum. They are widely used in technologies of casting such as sand casting, chill casting or pressure die casting. As their main characteristics we can include: very good castabillity, corrosion resistance, high mechanical properties and good thermal and electrical conductivity. Thanks to all these properties, the cast aluminum alloys have been used in various industries such as: automotive, engineering, heat exchangers or conductive elements. The last application requires a specific conditions of the process and the optimal chemical composition of the alloy, which allows to obtain high values of conductivity. The paper presents a study covering the impact of silicon content and heat treatment parameters on the electrical conductivity and mechanical properties (hardness HB) hypoeutetic silumin alloys such as AlSi11Mg, AlSi7Mg and AlSi5Mg. The aim of the study was to determine the optimal conditions for heat treatment parameters of various alloys providing to the most favorable mechanical and electrical properties.

PL

Siluminy, czyli stopy aluminium z głównym dodatkiem w postaci krzemu, są jednymi z najczęściej stosowanych typów stopów odlewniczych na bazie aluminium. Są one wykorzystywane w szeregu technologiach odlewniczych takich jak: odlewanie piaskowe, kokilowe czy odlewanie nisko lub wysoko ciśnieniowe. Do podstawowych własności tej grupy stopów możemy zaliczyć bardzo dobrą lejność, odporność na działanie środowiska korozyjnego, wysokie własności mechaniczne oraz dobrą przewodność cieplną i elektryczną. Dzięki tym własnościom, główne zastosowanie odlewów z siluminów to przemysł samochodowy, maszynowy, elementy konstrukcyjne, wymienniki ciepła czy elementy przewodzące prąd elektryczny. Ta ostatnia aplikacja wymaga zapewnienia szczególnych warunków procesu technologicznego oraz odpowiedniego składu chemicznego stopu, tak aby uzyskać wysokie wartości przewodnictwa. W pracy przedstawiono badania obejmujące wpływ zawartości krzemu oraz parametrów obróbki cieplnej na przewodność elektryczną i własności mechaniczne (twardość HB) siluminów podeutektycznych typu AlSi11Mg, AlSi7Mg oraz AlSi5Mg. Celem badań było określenie optymalnych warunków obróbki cieplnej poszczególnych stopów umożliwiających uzyskanie najkorzystniejszych własności mechanicznych i elektrycznych.

5

Aluminium composite casting dispersion reinforced with iron-aluminium and silicon carbide phases

Formanek B., Piątkowski J., Szymszal J.

Archives of Foundry Engineering

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2010

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Vol. 10, iss. 4

35--38

EN

Aluminium matrix composite with dispersion-reinforced, made by similar to stircasting process was characterised. The mixture of powders was produced by the process of mechanical agglomeration of powdered FexAly and SiC with aluminium. The chemical composition of agglomerates was selected in a way such as to obtain 25 wt.% reinforcement of the AlSi9Cu4 silumin matrix. Applying thermal analysis ATD, the alloy solidification process was determined, reading out the typical solidification parameters. The methods of light and scanning microscopy were used to reveal the structure of composite casting. Changes in chemical composition and phase composition of particles of the FeAl intermetallic phase in aluminium matrix were confirmed. The structure of silumin casting with matrix containing microregions of ceramic and intermetallic phases, typical of hybrid reinforcements, was obtained.