漂珠/AZ91D复合材料微观组织与性能的研究

Study on Microstructure and Properties of Fly Ash Cenosphere/AZ91D Composites

摘要:

采用搅拌铸造法,向镁合金熔体中添加漂珠,制备了漂珠/AZ91D复合材料,研究了该复合材料微观组织的均匀性、相组成、力学性能和阻尼性能。结果表明,漂珠在基体中分布均匀,无偏聚现象。在复合材料制备过程中,漂珠与镁合金熔体发生反应并被填充,使得复合材料中有Mg₂Si和MgO相生成。与基体合金相比,复合材料的力学性能和阻尼性能均得到明显提高。复合材料的断裂是以解理断裂为主的脆性断裂,在断裂过程中漂珠壁被撕裂。复合材料的阻尼机制主要是位错阻尼和界面阻尼。

Abstract:

Using stir casting method, fly ash cenosphere/AZ91D composites were fabricated by adding fly ash cenospheres into magnesium alloy melt, and the microstructure uniformity, phase composition, mechanical properties and damping properties of the composites were studied. The results showed that the fly ash cenospheres distributed uniformly in the matrix, without segregation phenomenon. In the preparation process of the composites, the cenospheres reacted with the magnesium alloy melt and were filled in by the melt. Mg₂Si and MgO phases formed in the reaction. Compared with the matrix alloy, the mechanical properties and damping properties of the composites are obviously improved. The cleavage fracture occurs when the composites fail, indicating that the fracture is brittle fracture. The walls of the cenospheres are torn in the process of fracture. The damping mechanisms of the composites are mainly dislocation damping and interface damping.