A nanoindentation study on Al₃Ni interface of Ni reinforced aluminum-silicon composite

ABSTRACT

Aluminum-silicon (AlSi) composite reinforced with 20 wt% Ni particulates was produced by hot pressing and characterized using nanoindentation. Energy dispersive spectrometry and X-ray diffraction analyses showed that Al₃Ni intermetallic was formed in the interface between Ni particulates and AlSi matrix. Chemical composition, hardness, and elastic modulus were studied along the interface from inner (near Ni) to outer (near AlSi) regions. A uniform composition was found throughout the interface, having 805.6 HV hardness and elastic modulus of 185.4 GPa. Interface properties have a crucial influence on the composite performance and their assessment is of paramount importance on composite properties estimation using predictive models.

KEYWORDS:

• Al₃Ni
• aluminum matrix composite (AMC)
• intermetallics
• nanoindentation
• nickel particles
• powder metallurgy

Funding

This work was supported by a Fundação para a Ciência e a Tecnologia (FCT) grant (SFRH/BPD/112111/2015) and by the projects EXCL/EMS-TEC/0460/2012 and UID/EEA/04436/2013.