Fe3Si金属间化合物高温抗氧化性能研究

摘要

Fe3Si intermetallic was prepared using vacuum are melting. The oxidation products of Fe3Si intermetallic were characterized by XRD, SEM, EPMA. Meanwhile,Fe3Si oxidation resistances were studied at temperature 800℃ and 900℃. The results show that the oxidation resistance of Fe3Si intermetallie is better than AISI 304 stainless steel at temperature 800℃ and 900℃. The oxidizing dynamics curves of Fe3Si was complex curves conforming to parabolic rule and linear rule at temperature 800℃. But at temperature 900℃ it was single parabolic curves. The initial growth mechanism of oxide layer was diffusion process of Si at temperature 800℃, and then with the crumbling of oxide layer, the growth mechanism was diffusion process of Si. The process of the oxidation kinetics was controlled by diffusion process at 900℃. Diffusion process of Si played a leading role in growth mechanism of oxide layer, with a mass transfer of Fe moved away from SiO2 of film.%采用电弧熔炼法制备了Fe3Si金属间化合物.选用AISI 304不锈钢作对比,研究了Fe3Si在800℃和900℃空气环境中的高温抗氧化性能,利用XRD,SEM,EPMA等测试设备对Fe3Si金属间化合物进行了表征.结果表明:在800℃,900℃下,Fe3Si金属间化合物都表现出较AISI 304不锈钢更好的高温抗氧化性能.其在800℃的氧化动力学近似表现为抛物线、线性复合规律,900℃下则转变为单一的二次抛物线规律.800℃下,Fe3Si初始的氧化膜生长机制受Si的扩散过程控制,而后因氧化膜剥落严重而转变为Si的氧化反应控制;900℃下,Fe3Si的氧化动力学过程主要受扩散过程控制,Si的扩散是氧化膜生长机制的主因,辅有Fe从SiO2膜向外扩散的传质过程.