Effect of rare earth elements on the microstructure of Mg-Al alloys

• Autorzy: Rzychoń, T. , Kiełbus, A.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The automotive use of magnesium is currently restricted to low-temperature structural components. Rare earth additions such as Ce, Nd, La and Pr are known to improve the creep performance. The aim of the research was to determine the effect of rare earths elements on the as-cast microstructure of magnesium alloys containing 4 wt% aluminum. Design/methodology/approach: The study was conducted on Mg-4Al-2RE (AE42) and a new Mg-4Al-4RE (AE44) alloys in the as-cast condition. The microstructure was characterized by optical microscopy (Olympus GX-70) and a scanning electron microscopy (Hitachi S3400) equipped with an X-radiation detector EDS (VOYAGER of NORAN INSTRUMENTS). The phase identification of these alloys was identified by X-ray diffraction (JDX-75). Findings: The microstructure of AE42 alloy consists of α-Mg solid solution with divorced eutectic Mg17Al12 + α-Mg, RE-rich phases and Mn-rich phase. The increase of RE contents from 2 wt% to 4 wt% leads to a change of microstructure of these alloys. In AE44 alloy was observed globular, lamellar and acicular precipitations of Al11RE3 and Al3RE phases. Moreover, there was found globular Mn-rich phase existence, but the Mg17Al12 phase was not observed. Research limitations/implications: The increase of RE content to 4 wt% caused the formation of new phases in the microstructure and prevented the formation Mg17Al12 phase. These factors can improve the creep resistance of the Mg-Al-RE alloys. The future research will contain creep tests and microstructural investigations of cast and die-cast alloys using TEM microscopy. Practical implications: The improvement of creep resistance of Mg-Al alloys can cause their application in automotive industry on the elevated-temperature structural components (above 150°C). Results of investigation may be useful for preparing die casting technology of the Mg-Al-RE alloys. Originality/value: paper includes the results of microstructural investigations of new AE44 magnesium alloy for die casting technology.

Słowa kluczowe

PL

stopy metaliczne; stopy ziem rzadkich; mikrostruktura

EN

metallic alloys; magnesium-aluminum-rare earth alloys; microstructure

• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 17, nr 1-2
• Strony: 149--152
• Opis fizyczny: Bibliogr. 16 poz., rys., tab., wykr.

Twórcy

autor

Rzychoń, T.

• Faculty of Materials Science and Metallurgy, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice. Poland,

autor

Kiełbus, A.

• Faculty of Materials Science and Metallurgy, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice. Poland

Bibliografia

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