FexCr5Al合金在模拟失水事故下的氧化行为研究
Oxidation Characteristics of FexCr5Al Alloys Under Simulated Loss of Coolant Accident Condition
张文怀 1姚美意 1林晓冬 2王皓瑜 1梁雪 2李毅丰 2胡丽娟 1谢耀平1
作者信息
- 1. 上海大学材料研究所,上海 200072
- 2. 上海大学微结构重点实验室,上海 200444
- 折叠
摘要
本研究熔炼制备了 4种FexCr5Al(x=13、15、17、18,质量分数,％)合金,采用配有蒸汽发生器的热重分析仪研究了 4种合金在1000和1200 ℃蒸汽中氧化2 h的行为.采用XRD、FIB/SEM、EDS和TEM观察分析腐蚀后样品的显微组织、晶体结构和成分.结果表明,4种合金在两种温度下氧化时,氧化动力学曲线均遵循抛物线规律,增加Cr含量合金的抛物线速率常数降低,改善了合金的抗高温蒸汽氧化性能;4种合金的氧化膜均为脊状形貌,主要由α-Al2O3组成.随Cr含量的增加,氧化膜中的孔隙减少,氧化膜与基体的结合性变好,说明增加Cr含量可以提高氧化膜的致密性和结合力,有助于形成均匀且致密的Al氧化膜,从而提高合金的抗高温蒸汽氧化性能.
Abstract
FexCr5Al(x=13,15,17,18,wt％)alloys were prepared and exposed to high temperature steam at 1000 and 1200℃ for 2 h.The high temperature oxidation behavior of the alloys was studied by a simultaneous thermal analyzer.The microstructure and composition of the oxide film after oxidation were analyzed by XRD,FIB,EDS and TEM.It is found that the oxidation kinetics of the alloys at two temperatures follow a parabolic growth law.The parabolic rate constants of the alloys are decreased with the increase in Cr content,and the high temperature steam oxidation resistance of the alloys are improved.The ridged oxide films mainly composed of α-Al2O3 are observed in the four alloys.In comparison with the low Cr alloy,the pores of the oxide film are reduced,and the bonding force of the oxide/matrix interface is improved in the high Cr alloy.Consequently,the compactness and adhesion of the oxide film are improved by increasing the Cr content,which promotes the formation of a dense Al oxide film and enhances the high temperature steam oxidation resistance of the alloy.
关键词
FeCrAl合金/高温蒸汽氧化/显微组织/氧化膜Key words
FeCrAl alloy/high temperature steam oxidation/microstructure/oxide film引用本文复制引用
出版年
2024
NETL
NSTL
万方数据