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This paper presents the first report of ultrasonic treatment (UST) assisted casting of independent 2D layered hexagonal boron nitride (hBN) reinforced aluminum matrix composites. A linear enhancement of nucleation density is obtained with treatment time from 0 to 90 s from dispersion of hBN platelets by UST. Outstanding grain refinement of 72% from 375.3 to 103.6 μm is obtained from UST for 90 s. The corresponding nanohardness is 709.2 MPa, a hardening of 36% due to symbiotic refinement and dispersion contributions. Anchoring and orientation of hBN platelets dictate that the elastic modulus improved up to 150% by ultrasonication for 90 s. The exfoliated 2D reinforcement layers reduce the coefficient of friction during sliding wear by 15% and loss of worn material by 46% in these composites. The mechanism of dispersion, improvement of properties, and quantitative correlations constitute a step of advancement towards understanding the role of 2D particle morphology and dimensionality on the ultrasonic casting of metal matrix composites. [ABSTRACT FROM AUTHOR] more...