(1. 中南大学材料科学与工程学院，长沙 410083；
2. 中南大学有色金属材料科学与工程教育部重点实验室，长沙 410083)
摘 要: 316L奥氏体不锈钢(简称316L钢)具有优良的高温力学、耐侵蚀等性能，在航空、核能等领域具有广泛应用。然而，316L钢在高温氧化环境下长期服役时，易产生开裂、剥落等缺陷而失效。采用热轧复合、退火热处理和原位氧化的方式在316L钢表面制备了Fe-Al/Al2O3高温抗氧化涂层，利用XRD、SEM、EDS等手段对试样的物相组成和组织形貌进行了表征，对比研究含有Fe-Al/Al2O3涂层的试样和316L钢的高温氧化行为。结果表明：316L钢和纯铝箔经热轧后，复合板界面的平均结合强度为54.47 N/mm2；铝/钢复合板经不同温度退火6 h后，发现750 ℃退火试样扩散层的厚度急剧增加，几乎占据全部铝层；选择750 ℃退火试样进行1 h的原位氧化，制得了Fe-Al/Al2O3涂层，其截面结构由表及里依次为Al2O3、FeAl2、FeAl、α-Fe(Al)和Fe；原位氧化试样和316L钢分别经900 ℃空气氧化72 h后，发现二者的氧化过程均符合抛物线规律，而原位氧化试样氧化质量的增加仅为316L钢的1/11，具有优良的高温抗氧化性能。
关键字: Fe-Al/Al2O3涂层；热轧复合；退火热处理；原位氧化；高温氧化行为
（1. School of Materials Science and Engineering, Central South
University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Metal Materials
Science and Engineering, Ministry of Education, Central South University,
Changsha 410083, China）
Abstract:Fe-Al/Al2O3 high-temperature anti-oxidant coating was prepared on the surface of 316L steel by hot-rolling composite, annealing heat treatment and in-situ oxidation. The specimens were characterized by using SEM, EDS and XRD, respectively. Meanwhile, the high-temperature oxidation behavior of the in-situ oxidized specimens containing Fe-Al/Al2O3 coating and 316L steel was investigated comparatively. The results show that the hot-rolled composite plate obtained by holding 316L steel and pure aluminum is well bonded, and the average bond strength of composite plate is obtained as 54.47 N/mm2. Then, the composite plate is held at different temperatures for 6 h for annealing heat treatment. The specimens preferably annealed at 750 ℃ for 6 h with optimum thickness were selected to be oxidized in-situ for 1 h. The Fe-Al/Al2O3 coating is obtained, and its cross-sectional structures in order from the surface to the inside are Al2O3, FeAl2, FeAl, α-Fe(Al) and Fe. When the in-situ oxidized specimen and 316L steel were oxidized at 900 ℃ for 72 h, the oxidation process of them conforms to the parabolic law together. While the oxidation mass gain of the in-situ oxidized specimen is only 1/11 of that of 316L steel, which has excellent high temperature oxidation resistance.
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