Mechanical properties of a squeeze cast Mg-Al-Sr alloy

• Autorzy: Trojanová Z. , Drozd Z. , Lukáč P. , Chatey A.
• Języki publikacji: PL

Abstrakty

EN

Purpose: The aim of the present work is to study the influence of temperature on tensile properties of the magnesium alloy AJ50, and to discuss possible hardening and softening mechanisms and thermally activated processes. Design/methodology/approach: Deformation behaviour of a Mg-Al-Sr magnesium alloy has been studied in tension as well as compression in the temperature interval from room temperature up to 300°C. Stress relaxation tests were performed with the aim to find applied stress components (internal stress and effective stress) and parameters of the thermally activated process/-es. Findings: The yield stress as well as the maximum stress of the alloy are very sensitive to the testing temperature. The work hardening coefficient O=dδ/dε decreases with increasing stress and temperature. Performed analysis of the O-α plots determined the hardening and softening mechanisms operating during the deformation. The internal stress decreses with increasin temperature, while the effective stress component increases. Practical implications: Estimated values of the activation volume as well as the activation energy indicate that the main thermally activated process is connected with the rapid decrease of the internal stress. Originality/value: An analysis showed that the main hardening process is the storage of dislocations at impenetrable obstacles. The activation

Słowa kluczowe

PL

własności mechaniczne; stopy magnezu; hartowanie; termiczna aktywacja

EN

mechanical properties; magnesium alloy; stress relaxation; hardening; thermal activation

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2008
• Tom: Vol. 29, nr 2
• Strony: 97--104
• Opis fizyczny: Bibliogr. 19 poz.

Twórcy

autor

Trojanová Z.

autor

Drozd Z.

autor

Lukáč P.

autor

Chatey A.

• Department of Physics of Materials, Faculty Mathematics and Physics, Harles University, Prague, Ke Karlovu 5, CZ-121 16 Praha 2, Czech Republic,

Bibliografia

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