Influence of nano hexagonal boron nitride on the wear properties of aluminium alloy

ABSTRACT

Spark plasma sintered, AA7050 reinforced with nano hexagonal boron nitride (n-h-BN) particles followed by characterisation research was carried out to determine the impact of h-BN in the aluminium matrix. With the aid of field-emission scanning electron microscopy , the uniform dispersion of hexagonal boron nitride was examined, and the impact of altering h-BN concentration on the mechanical and tribological properties was studied. In order to achieve individual dispersion of h-BN particles at low milling time without causing any structural damage, pre-mixing of powders prior to high-energy ball milling proved beneficial. Using the X-ray diffraction method, structural and phase analysis was performed on the powders as well as sintered samples. Pin-on disc apparatus is used for testing the weight loss of the composites. SEM was used to examine the worn surfaces of the substrate. According to the wear analysis, adding reinforcement with 0.5 wt% h-BN resulted in a 65% reduction in wear rate and a 33% increase in hardness. It has been found that h-BN tends to aggregate in composite powder above 0.5 wt%, reducing its physical and mechanical qualities.

KEYWORDS:

• Nanocomposites
• powder metallurgy
• spark plasma sintering
• hexagonal boron nitride
• aluminium alloy
• metal matrix composites
• nano powders

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the CHRIST University Monograph funding [MNGDFE - 1915].