Mechanical properties of magnesium alloy AZ91 at elevated temperatures

• Autorzy: Čížek L. , Greger M. , Dobrzański L. A. , Juřička I. , Kocich R. , Pawlica L. , Tański T.
• Języki publikacji: EN

Abstrakty

EN

Purpose: Purpose of this article is to extend a complex evaluation of magnesium alloys which requires very often knowledge of elastic-plastic properties at elevated temperatures. These properties are connected with microstructure that is influenced by metallurgical and technological factors and conditions of exploitation. Design/methodology/approach: Methodology Testing of magnesium alloys was based on tensile test in dependence on temperature. The methods of the light microscopy and SEM for metallographic and fracture analyses of alloys after testing were used. Findings: Objective of this work consisted in determination of changes of elastic-plastic properties of magnesium alloy AZ91 in dependence on temperature, including investigation of fracture characteristics. It was confirmed that during heating at chosen temperatures there occurs partial dissolution of minority phases. Homogenisation of microstructure is, however, accompanied by simultaneous forming of inter-granular non-integrities, which is unfavourable from the viewpoint of strength and plastic properties, especially at higher temperatures. Failure occurs practically at all temperatures basically by inter-crystalline splitting along the boundaries of original dendrites. At temperature testing near melting point of alloy the interdendrite areas melting were observed. Research limitations/implications: The experiment was limited by occurrence a void in cast alloys. Practical implications: The results may be utilized for a relation between plastic and strength properties of the investigated material in process of manufacturing. Originality/value: These results contribute to complex evaluation of properties magnesium alloys at higher temperatures namely for explanation of fracture mechanism near the melting point.

Słowa kluczowe

EN

mechanical properties; magnesium alloys; tensile test at elevated temperatures; fracture characteristics

PL

właściwości mechaniczne; stopy magnezu; test na rozciąganie w podwyższonych temperaturach; charakterystyka pękania

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 18, nr 1-2
• Strony: 203--206
• Opis fizyczny: Bibliogr. 15 poz., rys., wykr.

Twórcy

autor

Čížek L.

• Faculty of Metallurgy and Materials Engineering, Technical University of Ostrava, Tř. 17 Listopadu 15, 708 33 Ostrava, Czech Republic

autor

Greger M.

• Faculty of Metallurgy and Materials Engineering, Technical University of Ostrava, Tř. 17 Listopadu 15, 708 33 Ostrava, Czech Republic

autor

Dobrzański L. A.

• Division of Materials Processing Technology and Computer Techniques in Materials Science, Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland

autor

Juřička I.

• Ferona- Steel Servis Centrum, Czech Republic

autor

Kocich R.

• Faculty of Metallurgy and Materials Engineering, Technical University of Ostrava, Tř. 17 Listopadu 15, 708 33 Ostrava, Czech Republic

autor

Pawlica L.

• Faculty of Metallurgy and Materials Engineering, Technical University of Ostrava, Tř. 17 Listopadu 15, 708 33 Ostrava, Czech Republic

autor

Tański T.

• Division of Materials Processing Technology and Computer Techniques in Materials Science, Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland

Bibliografia

• [1] ASM Specialty Handbook- Magnesium and Magnesium Alloys, ed. Avedesian M., Baker H., ASM International, USA, 1999, 3-84.
• [2] J.R Davis, Metals Handbook, Desk. Edition, Second Edition, ASM International, The Materials Information Society, USA, 1998, 560-564.
• [3] L. Ptáček, Magnesium alloys- present state of development and exploitation, Proceedings of conference “METAL 2001”, Ostrava-Hradec n. Moravicí, 2001, 1-12, (in Czech).
• [4] K.A. Dahle, Z.C. Lee, M.D. Nave, P.L. Schaffer, D.H. Johnson, Development of the as-cast microstructure in magnesium-aluminium alloys, Journal of Light Metals 1, 2001, 61-73.
• [5] P. Palček, P. Lukáč, M. Chalupová, Z. Trojanová, Influence of temperature on fracture characteristics selected magnesium alloys, Conference “Degradation of structural materials ́2005”, Tĕrchová-Biely Potok, 2005, Publication in Materiálove Inžinierstvo (Materials Engineering), 3, 2005, 7-10 (in Slovak)
• [6] L.A. Dobrzański, T. Tański, L. Čížek, Influence of modification with chemical elements on structure of magnesium casting alloys. Proceedings of 13th International Scientific Conference “Achievements in Mechanical and Materials Engineering” AMME’2005, Gliwice-Wisla, 2005, 199-202.
• [7] L. Čížek, R. Kořený, I. Juřička, J. Maisner, M. Greger, s. Lasek, P. Beťáková, A. Hernas, Structure and Properties of the Selected magnesium Alloys, Proceedings of 10 th Jubilee International Scientific Conference “Achievements in Mechanical and Materials Engineering” AMME’2001, Gliwice-Zakopane, 2001, 75-78.
• [8] L.A. Dobrzański, T. Tański, L. Čížek, Influence of heat treatment on structure and mechanical property of the casting magnesium alloys. Proceedings of International Scientific Conference “Contemporary Achievements in Mechanics, Manufacturing and Materials Science” CAM3S’2005, Gliwice-Zakopane, 2005, 6 ps. (elektronic medium CD).
• [9] L. Čížek, M. Greger, L Pavlica, L.A. Dobrzański, T. Tański, Study of selected properties of magnesium alloy AZ91 after heat treatment and forming. In: Journal of Materials Processing Technology, 157-158, 2004, 466-471.
• [10] M. Greger, L. Čížek, A. Hernas, S. Rusz, R. Kocich, Tváření slitin hořčíku. Proceedings of conference “METAL 2004, Ostrava-Hradec nad Moravicí, 2004, Paper No. 167-6ps, (elektronic medium CD).
• [11] L. Čížek, M. Greger, R. Kocich, A Hernas, I Juřička, T. Tanski, Forming of AZ91 magnesium alloy after heat treatment. Sborník vĕdeckých prací VŠB TU Ostrava, řada hutnická, XLVII, 2005, 27-31.
• [12] M. Greger, Z. Jonšta, M. Widomska, R. Kocich, The experience at extrusion of magnesium alloy MgAl9Zn1 by equal channel angular pressing. In MECHATRONICS 2004. Warszawa, 172-174.
• [13] R. Kocich, Greger M. : Structure characteristics after hot rolling of AZ91 alloy, 6. Scientific Conference “Material in Engeneering” 2005, Herlany, 81-86, (in Czech).
• [14] M. Greger, L. Čížek, M. Widomska, Structural characteristics Magnesium Alloys along of the Equal Channel Angular Pressing. In: Advanced Metallic Materials and their joining, Bratislava 2004, 55-58.
• [15] L. Čížek, L. Pawlica, M. Greger, J. Pavelcová, T. Tański, Mechanical properties of the model casting magnesium alloy AZ 91, Proceedings of 11 th International Scientific Conference “Achievements in Mechanical and Materials Engineering” AMME’2002, Gliwice-Zakopane, 2002, 47-50.