空心陶瓷颗粒增强镁基复合材料的压缩行为研究

Study on Compression Behavior of Magnesium Matrix Composite with Hollow Ceramic Particles

通过搅熔铸造法制备了3%、6%、9%,平均粒径为100、150μm空心陶瓷增强镁合金复合材料（FAC/AZ91D）。研究了不同质量分数的空心陶瓷对该复合材料组织、密度、热膨胀系数和压缩性能等物理性能的影响,利用XRD分析了FAC/AZ91D复合材料的物相,界面形貌及成分由配置能谱分析（EDS）的扫描电镜（SEM）来分析。结果表明,空心陶瓷增强AZ91D镁合金复合材料的布氏硬度比基体有较大提高;通过Olympus对组织的观察发现,基体引入空心陶瓷后,组织细化,AZ91D镁合金铸态网状Mg17Al12消失;FAC/AZ91D复合材料在20~200℃的热膨胀系数低于基体,所制备的该复合材料室温压缩强度较基体有较大程度改善。

FAC/AZ91D composite was produced by compocasting technique by incorporating hollow ceramic in the molten AZ91D alloy with average particle size of 100 μm, 150μm, and 3% ,6% ,9%（all in wt.%）. The effect of different qualitative percentage of hollow ceramics on the microstructure, densities and coefficient of thermal expansion of the composite was investigated. The compressive properties of the composite was investigated. The microstructure of the composite was observed by using Olympus GX51 optical microscopy（OM） and scanning electron microscopes（SEM, Model JSM-6360LV） with energy dispersive spectrometer（EDS）. X-ray diffraction analysis was carried out to identify the phase in the composite samples. The results indicate that the microstructure of the composite becomes refine, and Brinell hardness is higher than matrix after adding hollow ceramic. At the same time, the meshy Mg17TAl12 disappears. The thermal expansion coefficients of the composite decreases, and the compressive strength of the composite improves at room temperature.