Effect of Cr and Mn addition and heat treatment on AlSi3Mg casting alloy

Journal Article · Sat Jan 14 23:00:00 EST 2017 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2016.11.022· OSTI ID:22689684

Tocci, Marialaura ^[1]; Donnini, Riccardo ^[2]; Angella, Giuliano ^[2]; Pola, Annalisa ^[1]

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1. Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze 38, 25123 Brescia (Italy)
2. National Research Council of Italy (CNR), Institute of Condensed Matter Chemistry and Technologies for Energy (ICMATE), Via R. Cozzi 53, 20125 Milan (Italy)

In the present paper the effect of heat treatment on an AlSi3Mg alloy with and without Cr and Mn addition was investigated. Beside the well-known modification of the morphology of Fe-containing intermetallics, it was found that Cr and Mn allowed the formation of dispersoids in the aluminium matrix after solution heat treatment at 545 °C, as shown by scanning transmission electron microscope observations. These particles were responsible of the enhanced Vickers microhardness of the aluminium matrix in comparison with the base alloy after solution treatment and quenching, according to dispersion hardening mechanism. The presence of these particles was not affected by ageing treatment, which instead allowed the precipitation of β-Mg{sub 2}Si, as shown by the elaboration of differential scanning calorimeter curves. The formation of dispersoids and the study of their effect on mechanical properties can represent an interesting development for applications at high temperatures of casting alloys due to their thermal stability compared to other strengthening phases as β-Mg{sub 2}Si. - Highlights: •Cr and Mn successfully modified the morphology of Fe-containing intermetallics. •Cr- and Mn-dispersoids formed in the aluminium matrix during solution treatment. •Dispersion hardening was detected after solution treatment for Cr-containing alloy. •The dispersion hardening effect was maintained after ageing treatment.

• OSTI ID: 22689684
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Vol. 123; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AGE HARDENING
AGING
ALUMINIUM ALLOYS
CASTING
CASTINGS
CHROMIUM ADDITIONS
COMPARATIVE EVALUATIONS
DISPERSION HARDENING
HEAT TREATMENTS
INTERMETALLIC COMPOUNDS
MAGNESIUM SILICIDES
MANGANESE ADDITIONS
MATRICES
MICROHARDNESS
MORPHOLOGY
QUENCHING
SOLUTION HEAT
TEMPERATURE RANGE 0400-1000 K
TRANSMISSION ELECTRON MICROSCOPY
VICKERS HARDNESS