Mechanical alloying during cryomilling of a 5000 Al alloy/AlN powder: the effect of contamination

• Published in: Journal of alloys and compounds Vol. 315; no. 1; pp. 276 - 283
• Main Authors: Goujon, C, Goeuriot, P, Delcroix, P, Le Caër, G
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 09-02-2001; Elsevier
• Subjects: Alloys; Applied sciences; Exact sciences and technology; Mechanical alloying; Metal powders; Metals. Metallurgy; Mössbauer spectroscopy; Nanostructures; Powder metallurgy. Composite materials; Production techniques; Nanostructures; Mechanical alloying; Alloys; Mössbauer spectroscopy; TDS; Aluminium base alloys; Temperature effect; Nitriding; Moessbauer spectrum; Experimental study; Iron alloy; Solid solution; Contamination; Metastable phase; Attrition mill; Time dependence; Magnesium alloy; Chemical composition; Oxidation; Powder grinding; Microstructure
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/S0925-8388(00)01303-7

Elemental powders of 80 vol% 5000 Al alloy (3 wt% Mg) and 20 vol% AlN were milled either in liquid nitrogen or at room temperature under argon. The milling of the mixture involved changes in the chemical composition: Fe contamination, oxidation and in-situ nitridation. The effects of milling time and temperature on the contamination of the system were analysed. Oxidation and in-situ nitridation were characterized by a LECO analyser and thermal desorption measurements, whereas Mössbauer spectroscopy was used to study the mechanical alloying of the Al alloy. The results show that a metastable solid solution of Mg and Fe in Al is formed during cryomilling. The occurrence of mechanical alloying in spite of the very low milling temperature is interpreted as a consequence of the fine crystallite size of the Al matrix.