FeAl多孔材料制备过程中烧结气氛对Al元素挥发及其抗水腐蚀的影响

Effect of sintering atmosphere on evaporation loss of Al and water-resistance corrosion in fabrication process of porous FeAl materials

以Fe、Al元素粉末为原料，采用粉末冶金法，通过偏扩散/反应合成烧结，制备FeAl金属间化合物多孔材料。通过 XRD、SEM、EDS 等表征手段，研究多孔试样烧结过程中基础元素的挥发及孔结构变化行为，并进行室温状态下的抗水腐蚀实验。结果表明，在1000~1300℃之间，随温度升高，试样在真空烧结过程中的质量损失率升高，在最终烧结温度为1300℃、保温4 h的条件下，质量损失率为10.5%；而试样在氩气氛烧结过程中，随温度升高试样质量几乎没有变化；氩气氛烧结条件下制备的 FeAl 多孔材料的抗水腐蚀性能明显优于真空条件下制备的多孔试样。氩气氛条件下烧结制备FeAl金属间化合物多孔材料能够避免真空烧结过程中Al元素的挥发，从而有效提高FeAl金属间化合物多孔材料的抗水腐蚀性能。

Porous FeAl materials were prepared by powder metallurgy through partial diffusion and reactive synthesis using Fe、Al mixture powder as raw materials. The evaporation behavior of element and pore structure changes of porous FeAl were characterised by the XRD、SEM、EDS, and the experiments of water-corrosion-resistant were carried at the room temperature. The results show that the mass loss rate increases with increasing final sintering temperature from 1 000 ℃ to 1 300 ℃ under the vacuum sintering;the mass loss rate is 10.5%at the final vacuum sintering temperature of 1 300 ℃ and holding for 4h;However,the mass loss rate of porous FeAl little change with increasing final sintering temperature under argon atmosphere sintering. The water-corrosion-resistant properties of the fabricated porous FeAl under the argon atmosphere is better than those under the vacuum atmosphere. The evaporation of Al element of porous FeAl materials can be restrained successfully in the process of high temperature argon atmosphere sintering, thus it can improve the water-resistance corrosion performance of porous FeAl.