Microstructural and mechanical properties of Al-Al2O3 micro and nanocomposite fabricated by stir casting

ABSTRACT

The current study examines the relationship between the microstructure and tribological characteristics of Al-Si alloy composites reinforced by secondary phase nano SiC particulates synthesis via the stir casting process. The results of wear testing of stir-cast SiC metal matrix composites including up to 12 weight percent fine (75–100 µm) and coarse (125–150 µm) size particles were obtained from cast aluminium alloy. It was discovered via microstructural investigation that the aluminium alloy and SiC particles have good interface bonding. However, at greater amounts (12 wt.%) of fine size reinforcement, clustering of reinforced particles is observed. In addition, results state that finer size particles agglomerate more in the matrix than coarser size particles at greater reinforcement levels. In addition, increasing the amount of SiC particles in the matrix enhanced the hardness of the base alloy. However, when the size of the SiC particles was reduced, the hardness of the composite increased dramatically. Better wear resistance was observed for higher SiC reinforcement levels, while higher forces were also associated with a corresponding increase in wear rate. A combined mode of adhesive and abrasive wear mechanisms is responsible for composite wear, according to a scanning electron microscopy (SEM) investigation of worn surfaces.

KEYWORDS:

• Al-Si matrix
• reinforced
• micro hardness
• microstructure
• wear
• optical microscope

Disclosure statement

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

Additional information

Funding

This research received no external funding.