The influence of Nd and Ho addition on the microstructure of Mg-7Al alloy

• Autorzy: Bryła K. , Dutkiewicz J. , Faryna M. , Dobatkina T. , Rokhlin L.
• Języki publikacji: PL

Abstrakty

EN

Purpose: of this paper was to examine effect of Nd and Ho on the microstructure of as-cast and solid-treated Mg-7Al alloy, and to study the response to ageing by hardness changes measurements of investigated alloys during aging at 200oC. Design/methodology/approach: The microstructure of Mg-7Al-3Nd and Mg-Al-10Ho alloys after casting and heat treatment was studied by means of metallographic and scanning electron microscopy. The phase characterisation was carried out by X-ray diffraction and by energy dispersive X-ray microanalyser. The hardness changes during aging of both alloys were determined by Vickers hardness. Findings: It was found that as-cast microstructure of Mg-7Al alloy doped with 3% Nd, and 10% Ho, is characterized by �ż-Mg solid solution with eutectic mixture of �α-Mg and Mg17Al12 phases, intermetallic compounds Al2Nd and Al11Nd3, and Al2Ho respectively. During solution heat treatment eutectic phase was dissolved and intermetallics were transformed into Al3Nd and Al3Ho, whilst Al11Nd3 phase was remained in microstructure. Aging of investigated alloys plays slight role in mechanical properties at ambient temperature. Research limitations/implications: The microstructure of supersaturated Mg-7Al-10Ho alloy is composed of ��α-Mg and thermally stable, fine and randomly distributed Al3Ho phase, what may considerably improve the creep behaviour this alloy at elevated temperature. The creep tests in connection with microstructural analysis will be done in the future. Practical implications: The development of creep resistant Mg-Al alloys with individual rare earth elements allows to apply these materials as responsible structural members working at elevated temperature. The present results extend the knowledge about effect of Nd and Ho addition on the microstructure of Mg-7Al alloys. Originality/value: Microstructural studies of two new Mg-7Al alloys doped with 3% Nd and 10% Ho were presented.

Słowa kluczowe

PL

Mg-Al-RE; odlew; obróbka cieplna; mikrostruktura

EN

Mg-Al-RE alloys; casting; heat treatment; microstructure

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2008
• Tom: Vol. 29, nr 1
• Strony: 40--44
• Opis fizyczny: Bibliogr. 15 poz.

Twórcy

autor

Bryła K.

autor

Dutkiewicz J.

autor

Faryna M.

autor

Dobatkina T.

autor

Rokhlin L.

• Institute of Technical Science, Pedagogical University, ul. Podchorążych 2, 30-084 Kraków, Poland,

Bibliografia

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