Reaction Pathways of Nanocomposite Synthesized in-situ from Mechanical Activated Al–C–TiO2 Powder Mixture

• Published in: Russian journal of non-ferrous metals 2018, Vol.59 (1), p.117-122
• Main Authors: Zarezadeh Mehrizi, Majid, Mostaan, Hossein, Beygi, Reza, Rafiei, Mahdi, Abbasian, Ahmad Reza
• Format: Article
• Language: English
• Subjects: Ceramic; Chemistry and Materials Science; Composite Materials; Materials Science; Metallic Materials; Refractory
• ISSN: 1067-8212; 1934-970X
• DOI: 10.3103/S1067821218010108

In-situ Al matrix composite was synthesized from Al–TiO 2 –C powder mixtures using mechanical alloying and heat treatment, subsequently. The effect of ball milling on reaction processes of the resulting nanocomposite was investigated. The evaluation of powder mixture without mechanical activation showed that at 900°C aluminum reduced TiO 2 , forming Al 3 Ti and Al 2 O 3 . After 20 h mechanical activation of powder mixture, Al 3 Ti and Al 2 O 3 were fabricated. After that, by increasing milling time up to 30 h, no new phases formed. The DTA analysis of 30 h milled powder indicated two peaks after aluminum melting at 730 and 900°C. The XRD results confirmed that at 730°C, molten Al reacted with TiO 2 and C, forming Al 3 Ti, Al 2 O 3 and Al 4 C 3 . After that, at 900°C, Al 3 Ti reacted with Al 4 C 3 , causing TiC formation. This results proposed that the TiC formation is associated by a series of reactions between intermediate products, Al 3 Ti and Al 4 C 3 and the resultant nanocomposite was successfully synthesized after 30 h milling and heated by DTA analysis up to 1200°C.