*Article* **Effect of Vibration Acceleration on Interface Microstructure and Bonding Strength of Mg–Al Bimetal Produced by Compound Casting**

**Feng Guan 1, Suo Fan 2,\*, Junlong Wang 1, Guangyu Li 1, Zheng Zhang <sup>1</sup> and Wenming Jiang 1,\***


**Abstract:** Vibration was adopted to enhance the interface bonding of Mg–Al bimetal prepared by the lost foam compound casting (LFCC) technique. The Mg–Al bimetallic interface was composed of three layers: layer I (Al3Mg2 and Mg2Si phases), layer II (Al12Mg17 and Mg2Si phases), and layer III (Al12Mg17 + δ-Mg eutectic structure). With the increase in vibration acceleration, the cooling rate of the Mg–Al bimetal increased, resulting in the decrease in the reaction duration that generates the intermetallic compounds (IMCs) layer (including layers I and II) and its thickness. On the other hand, the Mg2Si phase in the IMCs layer was refined, and its distribution became more uniform with the increase in the vibration acceleration. Finally, the shear strength of the Mg–Al bimetal continued to increase to 45.1 MPa when the vibration acceleration increased to 0.9, which was 40% higher than that of the Mg–Al bimetal without vibration.

**Keywords:** Mg–Al bimetal; vibration; interface; microstructure; bonding strength
