Synthesis of aluminum-based Metal Matrix Composites (MMCs) with lignite fly ash as reinforcement material (EN)

Vounatsos, PP (EN)

Moutsatsou, A (EN)

Koukouzas, N (EN)

Itskos, GS (EN)

In the present paper, two different lignite fly ashes (FAs) originated from Kardia, Northern Greece (KFA, Class C) and from Megalopolis, Southern Greece (MFA, Class F) were utilized for the fabrication of Al/fly ash Metal Matrix Composites (MMCs). Aluminum-fly ash and aluminum/silicon alloy (Al -12% Si) -fly ash mixtures containing 5%, 10% and 15% w/w fly ash were prepared and compacted. The products were tested for their thermal behavior and then sintered at 600°C for two (2h) and six hours (6h). The density and hardness of the sintered compacts were determined as a function of weight per cent of fly ash particles. Volume changes during sintering of green compacts were also estimated as a function of increasing fly ash weight per cent. Microscopic studies of green and sintered compacts were done to study the effectiveness of sintering. Additionally, the sintered compacts were characterized in terms of their chemical composition and mineralogical structure. Despite the higher porosity of the composites and the development of FA clusters in their metal matrix, there is a significant increase in hardness, especially for the high-calcareous KFAMMCs. Moreover, the results indicate that the density of the experimental products decreases by the increase of FA participation. The rise of Ca-Si and Si mineral phases is intense, particularly for the composites with the highest percentage presence of KFA (15%) and does not differentiate as a function of the sintering time. However, both the Al and Al-Si MMCs that underwent 2h sintering demonstrate higher hardness than the 6h-sintered. (EN)

conferenceItem (EN)

Green compacts (EN)

Calcium (EN)

Aluminum (EN)

Coal ash (EN)

Aluminum/silicon (EN)

Northern Greece (EN)

Reinforcement materials (EN)

Fly ash (EN)

Aluminum powder metallurgy (EN)

MMCs (EN)

Reinforcement (EN)

Silicon (EN)

Mineral phasis (EN)

Lignite fly ash (EN)

Chemical compositions (EN)

Sintering time (EN)

Thermal behaviors (EN)

Class-f (EN)

Powder metallurgy (EN)

Hardness (EN)

Metal matrices (EN)

Aluminum-based materials (EN)

Microscopic study (EN)

Silicon alloys (EN)

Lignite (EN)

Metallic matrix composites (EN)

Sintering (EN)

Metal matrix composites (EN)

Volume change (EN)

Powder metals (EN)

Sintered compacts (EN)

Metallurgy (EN)

Fly ash mixtures (EN)

Εθνικό Μετσόβιο Πολυτεχνείο

Ψηφιακό Αποθετήριο της Κεντρικής Βιβλιοθήκης του ΕΜΠ | Dspace@NTUA

Κεντρική Βιβλιοθήκη Ε.Μ.Π.

Ιδρυματικό Αποθετήριο

Δημοσιεύσεις μελών Δ.Ε.Π. σε συνέδρια

3rd World of Coal Ash, WOCA Conference - Proceedings (EN)

2009 (EN)

http://hdl.handle.net/123456789/35860