Al含量对漂珠/镁合金可溶复合材料组织与性能的影响

采用搅拌铸造法制备了不同Al含量下的漂珠（FAC）/镁合金可溶复合材料。采用金相显微镜、SEM及XRD观察分析了FAC/镁合金可溶复合材料的微观组织、溶解表面形貌及溶解产物的物相组成，采用力学性能试验机研究了复合材料的压缩性能，采用电化学工作站对复合材料进行电化学性能测试，在常温及水浴锅内进行复合材料在不同温度下的KCl溶液中的溶解试验。结果表明：该FAC/镁合金可溶复合材料主要由α-Mg基体相、β-Mg₁₇Al₁₂相、Mg₂Si相和MgO相组成。随着Al含量的增加，FAC/镁合金可溶复合材料的溶解速率先变快后减慢，在80℃的3wt% KCl溶液中，含15wt% Al的FAC/镁合金复合材料溶解速率最快，为56 mg/（h·cm²）。Al-FAC/镁合金可溶复合材料的抗压强度随Al含量的增加先提高后下降，四种合金的抗压强度均大于300 MPa，最高强度达到372 MPa。

Effect of Al content on the microstructure and properties of fly ash cenospheres/Mg alloy dissolvable composites

The fly ash cenospheres(FAC)/Mg alloy dissolvable composites with different contents of Al were prepared by stirring cast method. Optical microscopy, SEM and XRD were used to study the microstructure, surface morphology after the dissolution and phases of the dissolution product of the FAC/Mg alloy dissolvable composites. The compression property of the FAC/Mg alloy composite was tested using a mechanical performance testing machine. The electrochemical properties were investigated using electrochemical workstation. The immersion tests of the composites were conducted in potassium chloride (KCl) solution at different temperatures. The results show that the FAC/Mg alloy dissolvable composites are mainly composed of α-Mg matrix, β-Mg₁₇Al₁₂ phase, Mg₂Si phase and MgO phase. The dissolving rate of the FAC/Mg alloy dissolvable composites first enhances and then weakens with the increase of the content of Al. When the content of Al is 15wt%, the FAC/Mg alloy composite has the fastest dissolving rate of 56 mg/(h·cm²) in 3wt% potassium chloride (KCl) at 80℃.The compression strength of FAC/Mg alloy dissolvable composites first increases and then decreases with the increase of Al content, and the compression strengths of the FAC/Mg alloy composites are higher than 300 MPa, the highest strength is 372 MPa.