摘要
The effect of iron addition on the microstructure, mechanical and magnetic properties of Al-matrix composite was studied. Mechanical mixing was used for the preparation of 0, 5%, 10% and 15% Fe-Al composites（mass fraction）. Mixtures of Al-Fe were compacted and sintered in a vacuum furnace at 600 °C for 1 h. X-ray diffraction（XRD） of the samples containing 5% and 10% Fe indicates the presence of Al and Fe peaks, while sample containing 15% Fe reveals Al and Al13Fe4 peaks. The results show that both densification and thermal conductivity of the composites decrease by increasing the iron content. The presence of iron in the composite improves the compressive strength and the hardness. The strengthening mechanism is associated with the grain refinement of the matrix and uniform distribution of the Fe particles, as well as the formation of Al13Fe4 intermetallic. The measured magnetization values are equal to 0.3816×10-3 A·m2/g for 5% Fe sample and increases up to 0.6597×10-3 A·m2/g for 10% Fe sample, then decreases to 0.0702×10-3 A·m2/g for 15% Fe sample. This can be explained by the formation of the diamagnetic Al13Fe4 intermetallic compound in the higher Fe content sample detected by XRD analysis.
研究铁对粉末冶金法制备铝基复合材料微观组织、力学性能及磁学性能的影响。利用机械混合制备含0,5%,10%和15%Fe(质量分数)的铝基复合材料。Al-Fe混合粉末经压制后在真空炉中600°C烧结1 h。XRD结果表明:在含有5%和10%Fe的试样中只有Fe和Al的衍射峰,而含有15%Fe的试样中则存在Al和Al13Fe4的衍射峰。实验结果表明:随着Fe含量的增加,材料的致密度和导热性变差。复合材料中的Fe可以提高其强度和硬度。材料的强化机制包括基体的晶粒细化,Fe颗粒的均匀分布以及Al13Fe4金属间化合物的形成。含有5%Fe试样的磁化强度为0.3816×10-3A·m2/g,对于含有10%Fe的试样,其磁化强度增加至0.6597×10-3A·m2/g,而对于含有15%Fe试样,其磁化强度降低至0.0702×10-3A·m2/g。这是由于在高铁试样中形成了反磁性的Al13Fe4金属间化合物导致磁化强度降低。
