The influence of ageing on structure and mechanical properties of WE54 alloy

• Autorzy: Kiełbus A.
• Języki publikacji: EN

Abstrakty

EN

Purpose: WE54 magnesium alloy offers attractive properties for aerospace and automotive industries. It reaches high specific strength, creep resistance and corrosion resistance up to a temperature of 250 degrees centigrade. The alloy contains 5%wt.Y, 1.7%wt.Nd and 0.55%wt.Zr. The strength of this alloy is achieved essentially via precipitation strengthening. Depending on the ageing temperature and time, the precipitation sequence in WE alloys has been reported to involve formation of phases designated beta", beta' and beta. The aim of the research was to determine the effect of ageing parameters on the microstructure and mechanical properties of WE54 magnesium alloy. Design/methodology/approach: Solution treatment was performed at 525 degrees centigrade/8h with water cooling. Ageing treatments were performed at 250 degrees centigrade/4-96h in air. The microstructure was characterized using Transmission Electron Microscope (TEM). The examination of the mechanical properties was conducted on an MTS-810 machine at two temperatures: ambient and 200 degrees centigrade. Hardness measurements by Vickers method were performed on a ZHV50 hardness tester. Findings: The microstructure of the WE54 alloy in as-cast condition consists of alpha-Mg phase matrix with some fine-dispersion precipitates of Mg2Y and Mg24Y5 intermetallic phases inside and on grain boundaries. After solution treatment followed by water-cooling, the intermetallic phases dissolve in the matrix. The ageing treatment caused precipitation of beta", beta' and beta 1 intermetallic phases. The best mechanical properties (Rm=333MPa, R0,2=257MPa, A5=6,3%) has a alloy with beta' intermetallic phase after ageing at 250 degrees centigrade/16h. Research limitations/implications: The future research will contain corrosion and creep tests of WE5 magnesium alloy. Practical implications: The established heat treatment parameters can be useful for preparing heat treatment technology of WE54 casts. Originality/value: The relationship between the ageing parameters, microstructure and mechanical properties in WE54 magnesium alloy was specified.

Słowa kluczowe

EN

metallic alloys; mechanical properties; WE54 magnesium alloy; ageing; structure

PL

stopy metaliczne; właściwości mechaniczne; stop magnezu WE54; starzenie; struktura

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 23, nr 2
• Strony: 27--30
• Opis fizyczny: Bibliogr. 15 poz., fot., rys., tab.

Twórcy

autor

Kiełbus A.

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

Bibliografia

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