Volume no :6, Issue no: -1, July and October (2012)

INFILTRATION OF NANO- AND NANO- PREFORMS USING AN ALLOY

Author's: M. RODRÍGUEZ-REYES, H. F. LÓPEZ, J. R. PARGA-TORRES, J. A. DÍAZ-GUILLEN, J. A. AGUILAR-MARTÍNEZ and M. M. CISNEROS
Pages: [47] - [69]
Received Date: November 11, 2012
Submitted by:

Abstract

In this work, nano-ceramic preforms containing either or were infiltrated by using an Al-Si-Mg alloy via pressureless reactive infiltration. In both systems, a relatively large fraction of the nano-reinforcements were exposed to reaction with the molten alloy. It was found that Mg in the vapour phase or in the Al-Si-Mg melt acts to reduce the or nanoparticles. Also, when a nitrogen atmosphere is present, is formed. Other reactions occur that result in the formation of AlN including amorphous Al-Mg-Si-O phases. It was found that the phase always forms in the system, which can be detrimental for the stability and properties of the reinforced composite. In contrast, in the the phase did not develop probably due to the presence of which inhibits its formation. In addition, reduced infiltration was observed in the system due to the presence of MgO and These phases possess low wettability and can make the infiltration process increasingly difficult. In contrast, the exhibited improved metal flow probably as a result of reactive infiltration between the amorphous nanoparticles when in contact with the molten metal. Finally, micro-hardness measurements indicated that these systems exhibit similar values for a given fraction of reinforcement regardless of the type and/or distribution of nanoparticles.

Keywords

Nano- nano- infiltration, metal matrix nano-composites, aluminum alloys.