The influence of age hardening on the microstructure of GA8 magnesium alloy

• Autorzy: Kiełbus A. , Adamiec J. , Cwajna J. , Paśko J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: GA8 magnesium alloy is a general purpose gravity sand casting alloy containing aluminum, zinc and manganese. Typically, it is used in aerospace, automotive or commercial casting applications particularly where there is no high temperature requirement. Particularly for elements of the car interior, car body, chassis and driving gears. The aim of this paper is to present the results of investigations on the microstructure of the GA8 magnesium alloy after precipitation hardening. Design/methodology/approach: The study was conducted on GA8 magnesium alloys in as-cast condition and after heat treatment. The microstructure was characterized by optical microscopy (Olympus GX-70) and a scanning electron microscopy (Hitachi S3400) equipped with an electron dispersive detector EDS (VOYAGER of NORAN INSTRUMENTS). To measure the stereological parameters, an image analysis program "AnalysisPro" was used. Findings: A cast of the GA8 magnesium alloy shows the presence of continuous and discontinuous precipitates of ß (Mg17Al12) phase at the solid-solution grain boundaries, Moreover, the occurrence of Mg2Si and Mn5Al8 phases has been provided. After solution treatment at 415°C the area fraction of continuous and discontinuous β phase precipitates decreased. After ageing at 170°C GA8 alloy is characterized by discontinuous β phase along the solid solution grain boundaries. Area fraction of this phase increased compared to supersaturated state. Research limitations/implications: Future researches should involve investigations of the influence of precipitation hardening parameters on the mechanical properties of GA8 magnesium alloy. Practical implications: The established precipitation hardening parameters can be useful for preparing heat treatment technology of the GA8 magnesium alloy. Originality/value: The relationship between the as cast structure, precipitation hardening parameters and Mg17Al12 phase morphology in GA8 magnesium alloy was specified.

Słowa kluczowe

EN

metallic alloys; heat treatment; GA8 magnesium alloy

PL

stop metaliczny; obróbka cieplna; stopy magnezu

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2007
• Tom: Vol. 28, nr 9
• Strony: 533--540
• Opis fizyczny: Bibliogr. 15 poz., il., wykr.

Twórcy

autor

Kiełbus A.

autor

Adamiec J.

autor

Cwajna J.

autor

Paśko J.

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

Bibliografia

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