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1

The effect of major alloying elements on the size of the secondary dendrite arm spacing in the as-cast Al-Si-Cu alloys

Djurdjevič M. B., Grzinčič M. A.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 1

19-24

EN

A comprehensive understanding of melt quality is of paramount importance for the control and prediction of actual casting characteristics. Among many phenomenons that occur during the solidification of castings, there are four that control structure and consequently mechanical properties: chemical composition, liquid metal treatment, cooling rate and temperature gradient. The cooling rate and alloy composition are among them most important. This paper investigates the effect of some major alloying elements (silicon and copper) of Al-Si-Cu alloys on the size of the secondary dendrite arm spacing. It has been shown that both alloying elements have reasonable influence on the refinement of this solidification parameter.

2

Analysis of influence of chemical composition of Al-Si-Cu casting alloy on formation of casting defects

Dobrzański L. A., Krupiński M., Zarychta P., Maniara R.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 21, nr 2

53-56

EN

Purpose: A methodology of the computer-aided determining relationship between chemical composition of aluminium alloy and castings quality was presented in the paper. Design/methodology/approach: To resolve the problem artificial neural networks were used. Classification problems were evaluated by the consideration mainly the values of mistakes and correct answers of networks for test data. On the basis of data analyzed by the neural network, which has the best quality classification of chemical composition of tested material, the concentration of alloying elements range, which have an effect on formation casting defects, were developed to eliminate them in the future. Findings: Combining of all methods making use of chemical composition of aluminium alloy and neural networks will make it possible to achieve a better casting quality. Research limitations/implications: The presented issues may be use, among others, for manufacturers of car subassemblies from light alloys, where meeting the stringent quality requirements ensures the demanded service life of the manufactured products. Originality/value: The correctly specified number of chemical composition of aluminium alloy enables such technological process control where the number of castings defects can be reduced by means of the proper correction of the process.

3

The effect of copper concentration on the microstructure of Al-Si-Cu alloys

Maniara R., Dobrzański L. A., Krupiński M., Sokołowski J. H.

Archives of Foundry Engineering

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2007

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Vol. 7, iss. 2

119-124

EN

In the metal casting industry, an improvement of component quality depends mainly on better control over the production parameters. In order to gain a better understanding of how to control the as-cast microstructure, it is important to understand the evaluation of microstructure during solidification and understanding how influence the changes of chemical concentration on this microstructure. In this research, the effect of Cu content on the microstructure and solidification parameters of Al-Si-Cu alloys has been investigated. Thus, the thermal analysis of the alloys is used to control of aluminum casting process. The effect of different Cu content on solidification parameters such: aluminum dendrites nucleation temperature (TLiq, Liquidus temperature), á+â eutectic nucleation temperature (TE(Al+Si)N), Cu-rich eutectic nucleation temperature (TAl+Cu), solidus temperature (Tsol), solidification range (ÄTs) has been studied in liquidus region. Influence of Cu content on the microstructure has been carried out. The principle observation made from this work ware that as copper concentration is increased the liquidus and solodius temperature decried. In addition to this it was observed that increase a Cu content from 1 to 4 wt % caused reduce of the secondary dendrite arm spacing and increase the grain size.

4

Quality analysis of the Al-Si-Cu alloy castings

Dobrzański L. A., Krupiński M., Maniara R., Sokolowski J. H.

Archives of Foundry Engineering

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2007

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Vol. 7, iss. 2

91-94

EN

The developed design methodologies both the material and technological ones will make it possible to improve shortly the quality of materials from the light alloys in the technological process, and the automatic process flow correction will make the production cost reduction possible, and - first of all - to reduce the amount of the waste products. Method was developed for analysis of the casting defects images obtained with the X-ray detector analysis of the elements made from the Al-Si-Cu alloys of the AC-AlSi7Cu3Mg type as well as the method for classification of casting defects using the artificial intelligence tools, including the neural networks; the developed method was implemented as software programs for quality control. Castings were analysed in the paper of car engine blocks and heads from the Al-Si-Cu alloys of the AC-AlSi7Cu3Mg type fabricated with the "Cosworth" technological process. The computer system, in which the artificial neural networks as well as the automatic image analysis methods were used makes automatic classification possible of defects occurring in castings from the Al-Si-Cu alloys, assisting and automating in this way the decisions about rejection of castings which do not meet the defined quality requirements, and therefore ensuring simultaneously the repeatability and objectivity of assessment of the metallurgical quality of these alloys.

5

Stront jako modyfikator stopów AlSi i AlSiCu.

Łatkowski A., Bronicki M., Gryziecki J.

Rudy i Metale Nieżelazne

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1999

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R. 44, nr 3

101-107

PL

Opierając się na analizie zmian mikrostruktury określono optymalne ilości strontu zapewniające efekt modyfikacji w stopach AK7, AK9, AK11, AK52 i AK 104. Zbadano również trwałość modyfikatora poprzez kolejne przetopy odlewów. Przeprowadzono badania wpływu ilości modyfikatora na udarność stopów.

EN

The optimum strontium amount for good modification of AK7, AK9, AK11, AK52, AK104 alloys was determined on the base of the analysis of microstructural changes. The stability of the modifier was investigated on the way of succesive remelting of billets. The influence of amount of modifier on the impact strength of the alloys was established.