草酸盐热分解法制备多孔FeNi合金粉及其热分解动力学

采用草酸盐热分解还原法制备了粒径1 mm的多孔结构FeNi合金粉，研究了草酸铁镍前驱体热分解过程. 结果表明，FeNi合金为纯BCC相，前驱体在加热过程中在217.5和352.5℃脱水和热分解释放出CO和CO2气体，产生多孔结构；前驱体热分解活化能为148.59 kJ/mol，热分解过程遵循随机成核和随后生长模型，指前因子为1.25×107，动力学方程为G(a)=[-ln(1-a)]0.44.

Preparation of Porous FeNi Alloy Powder by Oxalate Thermal Decomposition and the Kinetics

The porous FeNi alloy powder with a particle size of 1 mm and BCC structure was prepared by a thermal decomposition-reduction process of oxalate precursor, and the thermal decomposition process studied. The results showed that the precursor underwent two steps in the heating process, dehydration (217.5℃) and gas (CO and CO2) release (352.5℃), and the latter was the reason for the formation of porous structure. The thermal decomposition followed random nuclei production and nuclei growth model, the activation energy was 148.59 kJ/mol, the pre-exponential factor 1.25×107 and the kinetics function G(a)=[-ln(1-a)]0.44.