【作者】 郑海务；

【导师】 凤仪；

【作者基本信息】 合肥工业大学 ， 材料学， 2003， 硕士

【摘要】 泡沫铝是一种结构和功能一体化的材料。本文采用熔体发泡法，通过相关理论分析和控制发泡温度、搅拌时间、保温时间、调节发泡剂含量等制备出了孔结构基本可控、孔洞分布均匀的闭孔泡沫铝样品。在此基础上，研究了泡沫铝的动态力学性能以及导电、导热和电磁屏蔽等物理性能。 使用霍普金森压杆测试了泡沫铝试样的动态压缩性能。实验结果表明，泡沫铝的屈服强度随着应变率的增加而增加；应变对固体材料的应变率敏感度影响很小，但是泡沫铝的应变率敏感度不是常数，而是随着真应变的增加而增大，在同样的应变下，随着应变率变化幅度的增大而增大；泡沫铝的能量吸收随着应变率的增加而增加并且和泡沫铝的密度有关；泡沫铝的吸能效率随着应变率的增加略有下降。 研究了泡沫铝的导热系数和电导率与其微结构(孔隙率、孔径)的关系，结果表明随着孔隙率的增加，泡沫铝的导热系数、电导率都降低，而在孔隙率基本相同条件下孔径对于泡沫铝的导热系数与电导率影响很小，可以忽略不计。 测试了泡沫铝的电磁屏蔽效能。结果表明，在孔径相近时，随着孔隙率的增大，泡沫铝的屏蔽效能随之下降。当孔隙率相近时，随着孔径的增大，泡沫铝的屏蔽效能也下降。而厚度几乎对泡沫铝的屏蔽效能无影响。更多还原

【Abstract】 In this paper closed-cell foam samples with basically controllable pore structure and uniform distributed pore were prepared by means of melt foaming technique (MFT). By relative theory analysis and adjusting the content of foam agent, foaming temperature, stirring time and hold time, means of getting samples with high quality has been found. On the basis of these, properties of dynamic compression, thermal conductivity, electrical conductivity and electromagnetic shielding of foam samples (FS) were investigated.Dynamic compressive properties of FS were tested using split Hopkison compressive bar. The results showed that yielding the strength increase with the strain rate, the energy absorption increase with increasing strain rate and was related to the density. Strain has slightly effect on the strain rate sensitivity of the solid material, but the strain rate sensitivity of FS increase with increasing true strain and also increase with incremental change in strain rate at the same true strain.The properties of thermal conductivity, electrical conductivity and electromagnetic shielding were studied. The thermal conductivity and electrical conductivity have been both found to decrease with decreasing porosity, but the influence of cell diameter on these properties is almost negligible. The experimental results of electromagnetic shielding showed that its values are depend on porosity and cell diameter, with the increase of porosity and cell diameter, the property of electromagnetic shielding decrease.更多还原