Influence of the conditions of casting and heat treatment on the structure and mechanical properties of the AlMg10 alloy

• Autorzy: Kordas P.

Identyfikatory

DOI

10.5604/01.3001.0010.5137

• Języki publikacji: EN

Abstrakty

EN

Purpose: Assessment of the possibilities of shaping the structure and improvement of mechanical properties of casting from AlMg10 alloy through a selection of casting technology and precipitation hardening. Design/methodology/approach: the work evaluated the impact of casting and heat treatment technology on the mechanical properties and structure of AlMg10 alloy castings. The tests were performed on 200 mm × 100 mm × 25 mm plate castings produced by gravity casting methods for sand and metal moulds and by a liquid state press moulding technology. Castings made with these technologies solidify in substantially different heatevaporation conditions and exhibit varying degrees of primary structure fragmentation. Metallographic and strength tests were performed on raw castings and after heat treatment. Findings: The changes in the morphology and size of primary crystals and the dispersion of the reinforcing phase according to the casting solidification rate and the precipitation hardening treatment were analyzed. Solidifying castings in the form of sand show a globular structure, whereas in die and press castings, a typically dendritic structure occurs, with the dendritic crystals in pressed castings being much smaller in size than the die castings. In castings which were not heat-treated, the reinforcing phase of Al3Mg2 occurs in interdendritic spaces, and its dispersion increases with the rate of cooling. After supersaturation and ageing treatments, the phase α has a grain structure in all samples. The largest dispersion of reinforcing molecules is characterized by press castings. In a raw state, the highest mechanical properties are shown by castings made in the form of sand and the method of pressing in a liquid state. Heat treatment of AlMg10 alloy castings significantly influences the increase of mechanical indexes in all castings investigated. The highest features of Rm are approx. 330 MPa and A5 above 10% is obtained in castings made by the press method. Research limitations/implications: Particular attention should be paid to the avoidance of the effects of slag inclusion, shrinkage and magnesium oxidation during casting of AlMg10 alloys. In die castings of a plate type, due to own stresses, a significant decrease in mechanical properties occurs. Practical implications: The most advantageous mechanical properties of AlMg10 alloy castings are obtained by using liquid-state pressing technology. In addition, this technology makes it possible to produce thin-walled castings of high dimensional accuracy, high airtightness, fine grain structure, lack of surface defects and low roughness. Originality/value: The paper presents the possibility of improving the mechanical properties of AlMg10 castings by applying heat treatment. It has been proven that the casting method has a significant effect on the mechanical properties of the castings.

Słowa kluczowe

EN

aluminium-magnesium alloys; mechanical properties; heat treatment

PL

stopy aluminium; stopy magnezu; właściwości mechaniczne; obróbka cieplna

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2017
• Tom: Vol. 83, nr 1
• Strony: 26--32
• Opis fizyczny: Bibliogr. 12 poz., rys., tab.

Twórcy

autor

Kordas P.

• Department of Foundry Engineering, Faculty of Production Engineering and Materials Technology, Czestochowa University of Technology, Al. Armii Krajowej 19, 42-201 Czestochowa, Poland

Bibliografia

• [1] A.A. Canales, E. Carrera, J. Talamantes-Silva, S. Valtierra, R. Colas, Mechanical properties in as-cast and heat treated Al–Si–Cu alloys, International Journal of Microstructure and Materials Properties 7/4 (2012) 281-300.
• [2] S. Jayalakshmi, Q, Dezhi, S. Sankaranarayanan, M. Gupta, Microstructure and mechanical properties of Mg–Al alloys with in situ Al4C3 phase synthesised by CO2 incorporation during liquid state processing, International Journal of Microstructure and Materials Properties 8/4-5 (2013) 283-298.
• [3] Y. Kaygisiz, N. Marasli, Microstructural, mechanical and electrical characterization of directionally solidified Al–Si–Mg eutectic alloy, Journal of Alloys and Compounds 618 (2015) 197-203.
• [4] Y. Shu-qing, L. Xing-fu, The effect of Si morphology on the microstructure and wear property of ZA48 alloy, International Journal of Microstructure and Materials Properties 9/1 (2014) 88-96.
• [5] I. Luna, H. Molinar, M. Roman, J. Bocardo, M. Trejo, Improvement of the tensile properties of an Al–Si– Cu–Mg aluminium industrial alloy by using multi stage solution heat treatments, Materials Science and Engineering 561 (2013) 1-6.
• [6] A. Shokuhfar, O. Nejadseyfi, A comparison of the effects of severe plastic deformation and heat treatment on the tensile properties and impact toughness of aluminium alloy 6061, Materials Science and Engineering 594 (2014) 140-148.
• [7] M. Krupiński, K. Labisz, T. Tański, B. Krupińska, M. Król, M. Polok-Rubiniec, Influence of Mg addition on crystallisation kinetics and structure of the Zn–Al–Cu alloy, Archives of Metallurgy and Materials 61/2 (2016) 785-790.
• [8] M. Król, T. Tański, G. Matula, P. Snopiński, A.E. Tomiczek, Analysis of crystallisation process of cast magnesium alloys based on thermal derivative analysis, Archives of Metallurgy and Materials 60/4 (2015) 2993-3000.
• [9] S. Xia, M. Ma, J. Zhang, W. Wang, W. Liu, Effect of heating rate on the microstructure, texture and tensile properties of continuous cast AA 5083 aluminium alloy, Materials Science and Engineering 609 (2014) 168-176.
• [10] Z. Górny, J. Sobczak, Modern casting materials based on non-ferrous metal, Ed. ZA-PIS, Cracow, 2005 (in Polish).
• [11] Polish Standard PN-EN ISO 6892-1:2016-09 Metallic materials - Tensile testing - Part 1: Method of test at room temperature.
• [12] B. Wierzbicka, M.S. Soiński, Casting technology, Publishing House Politechnika Częstochowska, Częstochowa, 1996.

Uwagi

PL

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).