Journal ArticleDOI
Effect of composition on the microstructure and mechanical properties of Mg–Zn–Al alloys
TLDR
In this paper, three types of alloys were identified and characterized by Mg 32 (Al, Zn) 49, also known as the τ phase, MgZn phase, and a ternary icosahedral quasi-crystalline phase denoted as the Q phase, respectively.Abstract:
Magnesium is receiving great attention for transport applications, particularly its cast alloys. This investigation focuses on the as-cast microstructure and mechanical properties of permanent-mould cast Mg–Zn–Al alloys with typical compositions within the high zinc castable domain. Three types of alloys were identified and characterized by Mg 32 (Al, Zn) 49 , also known as the τ phase; MgZn phase, also known as the ɛ phase; and a ternary icosahedral quasi-crystalline phase, denoted as the Q phase, respectively. A schematic phase diagram is proposed to show the change of microstructral constituents with element content and the Zn/Al ratio. The diagram reveals that the microstructral constituent is dominated by both the content of Zn or Al and the Zn/Al mass ratio; alloys with a high Zn/Al ratio and a low Al content fall into the ɛ-type; alloys with an intermediate Zn/Al ratio and an intermediate Al content favour the τ-type; and those with a low Zn/Al ratio and a high Al are dominated by the icosahedral quasi-crystalline phase. No Mg 17 Al 12 (γ) phase was found in those ZA series alloys. The solidification process and its effects on the phase constituents were discussed. Preliminary mechanical property testing showed that all the experimental alloys possess comparable ultimate strength and yield strength with the AZ91 alloy at ambient temperature, but show far superior creep resistance at elevated temperatures. Moreover, while ambient-temperature properties solely depend on the total element contents, the τ- and the Q-type alloys show greater potential than the ɛ-type alloys on the improvement of elevated temperature properties.read more
Citations
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Microstructure and corrosion resistance of phytic acid conversion coatings for magnesium alloy
TL;DR: In this article, a new innoxious and pollution-free chemical protective coating for magnesium alloys, phytic acid conversion coating, was prepared, which is found to have high cover ratio and no cracks are found by atomic force microscopes (AFM) and scanning electron microscopy (SEM).
Journal ArticleDOI
Magnesium secondary alloys: Alloy design for magnesium alloys with improved tolerance limits against impurities
Carsten Blawert,Daniel Fechner,Daniel Höche,V. Heitmann,W. Dietzel,K.U. Kainer,P. Živanović,Christiane Scharf,André Ditze,Joachim Gröbner,Rainer Schmid-Fetzer +10 more
TL;DR: In this article, a new concept replacing the β-phase by τ-phase was proposed, which is able to incorporate more impurities while being electrochemically less detrimental to the matrix.
Journal ArticleDOI
Unraveling the effects of Zn addition and hot extrusion process on the microstructure and mechanical properties of as-cast Mg–2Al magnesium alloy
TL;DR: In this article, the effects of zinc addition and hot working via extrusion process on the microstructure and mechanical properties of as-cast Mg-2Al-xZn (x = 0, 0.5, 1, 2, and 5) magnesium alloys were studied.
Journal ArticleDOI
Effects of Sn content on the microstructure and mechanical properties of Mg-7Zn-5Al based alloys
TL;DR: In this article, the microstructures and tensile properties of the as-cast and heat treated Mg-7Zn-5Al based alloys with 1-6 wt.% Sn addition were studied.
Journal ArticleDOI
Effects of cerium on the microstructure and mechanical properties of Mg–20Zn–8Al alloy
TL;DR: In this paper, the effects of Ce on the microstructure and mechanical properties of the alloys were investigated, and the results showed that the dendrite as well as grain size were refined by the addition of Ce, and best refinement was obtained in 1.39% Ce containing alloy.
References
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Book
Ternary Alloys : A Comprehensive Compendium of Evaluated Constitutional Data and Phase Diagrams
TL;DR: In this article, the authors present the results of an international assessment program for alloy phase diagram data, coordinated by APDIC (the Alloy Phase Diagram International Commission), which meets the needs of the worldwide technical community to establish assessment priorities in relation to the technological requirements of industry and commerce and to also set quality standards for assessments.
Journal ArticleDOI
Creep and microstructure of magnesium-aluminum-calcium based alloys
TL;DR: In this article, a ternary intermetallic phase, (Mg,Al)2Ca, was identified in the microstructure of the ACX alloys and is proposed to be responsible for the improved creep resistance of the alloys.
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Effects of RE on the microstructure and mechanical properties of Mg-8Zn-4Al magnesium alloy
TL;DR: In this article, the effects of rare earth (RE) alloy element on the microstructure and mechanical properties of Mg-8Zn-4Al (ZA84) alloy have been investigated.
Journal ArticleDOI
A thermodynamic description of the Al-Mg-Zn system
TL;DR: In this article, a thermodynamic description of the Al-Mg-Zn system was developed based on critically evaluated experimental data, and three different thermodynamic models were applied to three different types of phases in this system, i.e., disordered solution phases, stoichiometric compounds, and semistoichiometric phases.
Journal ArticleDOI
The crystal structure of the equilibrium Φ phase in Mg–Zn–Al casting alloys
TL;DR: The crystal structure of the equilibrium intermetallic Φ phase formed in a Mg-Zn-Al casting alloy has been characterised using transmission electron microscopy as mentioned in this paper.