Abstract
The nano-SiC_p/ZA38 composites reinforced by nano SiC particles were fabricated by stirring assisted ultrasonic vibration. To establish the influence of the fusant temperature, stirring speed, and ultrasonic power on the mechanical and tribological properties of the cast nano-SiC_p/ZA38 composite material, orthogonal experiments in four different fusant temperatures, stirring speed, and ultrasonic power were conducted. The synergistic effects of the thermal-force-acoustic field aroused by melting, stirring, and ultrasonic vibration were investigated. It was observed that the wear rate decreased with the dimension of the primary dendrite arm spacing. The wear rate of fabricated composite material decreased to a minimum value of 0.0042 mm s^–1 when melting at 730 °C, stirring with a speed of 300 rpm and ultrasonic vibration with a power of 850 W. The hardness reached 163.9 HV, and the compression strength reached 803 MPa. It was concluded that the acoustic field works prominently in improving the mechanical properties of the nano-SiC_p/ZA38 composite, while the thermal and acoustic fields play a major part in the friction and wear properties. Thus, the force field gets converted into an assistant field. In addition, the simultaneously or solely increased thermal-force-acoustic field does not ensure a considerable enhancement in the mechanical and tribological properties of the nano-SiC_p/ZA38 composite.

Key words
composite, ultrasonic vibration, tribological property, microstructure, orthogonal experiment, acoustic field

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