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This study examined the effects of a pulsed magnetic field (PMF) on the solidified microstructure and properties of A357 aluminium alloy. Results showed that the solidified microstructure of the alloy treated by a PMF was refined. The treated alloy in the T6 state had superior mechanical properties, with the ultimate tensile strength, yield strength and elongation increasing by 48 MPa (18.5%), 46 MPa (16.4%) and 4.8% (142%), respectively, when compared with the untreated alloy. When testing at room temperature, with a strain amplitude of 1 × 10−4 and at a frequency of 1 Hz, the damping capacity value was 14.2 × 10−3 for the alloy subjected to a PMF treatment, which increased by nearly 170% when compared with the untreated alloy.

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Effect of discharging frequency of low voltage pulsed magnetic field (LVPMF) on the morphology and size of eutectic Si in eutectic Al–Si (Al–12Si) alloys has been investigated, and some characteristic parameters the characterised the microstructure of the eutectic Si phase were obtained. Dry sliding wear behaviour of eutectic Al–Si alloys without and with LVPMF treatment were also tested using a pin-on-disc wear testing machine, and scanning electron microscopy and energy dispersive spectroscopy X-ray of worn surfaces were carried out to determine the governing mechanisms in the eutectic Al–Si alloys without and with LVPMF treatment. The results show that the eutectic Si became smaller with the increase in discharging frequency. Fine short rod-like or rounded particle-like eutectic silicon with 2·3 μm in length, 0·6 μm in the width, and 3·8 in aspect ratio was formed in eutectic Al–Si alloy treated by 6 Hz LVPMF. The wear resistance of eutectic Al–Si alloys increased with the increase in discharging frequency. The adhesive wear was observed in eutectic Al–Si alloy without LVPMF treatment under normal load of 80 N. However, mainly abrasive was observed in eutectic Al–Si alloy with 6 Hz LVPMF treatment.