The effect of cooling rate on microstructure and mechanical properties of AC AlSi9Cu alloy

• Autorzy: Dobrzański L. A. , Maniara R. , Sokolowski J. H.
• Języki publikacji: EN

Abstrakty

EN

Purpose: In this work the effect of cooling rate on the size of the grains, SDAS, size of the β precipitation and thermal characteristic results of AC AlSi9Cu cast alloy have been described. The solidification process was studied using the cooling curve and crystallization curve at solidification rate ranging from 0,16 °Cs ^-1 up to 1,04 °Cs ^-1. Design/methodology/approach: The experimental alloy used in this investigation was prepared by mixing in suitable proportion the AC AlSi5Cu1(Mg) commercial alloys and two master alloys AlSi49 and AlCu55. Thermal analysis tests were made using the UMSA Technology Platform. Cooling curve thermal analysis was performed on all samples using high sensitivity thermocouples of K type that were protected in a stainless steel sheath and data were acquired by a high speed data acquisition system linked to a PC computer. Each chilled sample was sectioned horizontally where the tip of the thermocouple was located and it was prepared by standard grinding and polishing procedures. The final stage of polishing was done using commercial silicon oxide slurry. Optical microscopy was used to characterize the microstructure and intermetallic phases. Secondary dendrite arm spacing measurements were carried out using a Leica Q-Win ™ image analyzer. The UTM measurements were carried out using a Zwick testing machine. Findings: Increasing the cooling rate increases significantly the liquidus temperature, nucleation undercooling temperature, solidification range and decreases the recalescence undercooling temperature. Increasing cooling rate refines all microstructural features including secondary dendrite arm spacing (SDAS) and intermetallic compounds and improves silicon modification level. Research limitations/implications: The results presented in this paper show results only for the one alloy - AC AlSi9Cu, and for the assessment of the Silicon Modification Level didn't include the arrangement of a Si crystal in a matrix. Practical implications: The aim of this work is describe in detail the solidification process in a number of AC AlSi9Cu foundry alloy. Cooling rates applied in this experiment occur in cross section of a bloc engine. The results shows the effect of different cooling rates on the microstructural features and the characteristic parameters of the cooling curve of ACAlSi9Cu alloy. Originality/value: Original value of the work is applied the artificial intelligence for the assessment of the Silicon Modification Level.

Słowa kluczowe

EN

aluminum alloys; cooling rate; thermal characteristics; secondary dendrite arm spacing

PL

stopy aluminium; szybkość chłodzenia

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2007
• Tom: Vol. 28, nr 2
• Strony: 105--112
• Opis fizyczny: Bibliogr. 20 poz., il., wykr.

Twórcy

autor

Dobrzański L. A.

autor

Maniara R.

autor

Sokolowski J. H.

• Division of Materials Processing Technology, Management and Computer Techniques in Materials Science, Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland,

Bibliografia

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