高温合金Inconel 740H在空气和水蒸气环境中的氧化行为

Oxidation Behavior of High Temperature Alloy Inconel740H in Air and Water Vapor Environment

对Inconel740H高温合金在700、800、900℃分别进行空气和水蒸气环境下的高温氧化试验,采用热重法、X射线衍射、扫描电镜和能谱仪研究试样。结果表明：长时间空气氧化形成的氧化膜成分与长时间水蒸气的氧化膜类似,氧化物主要由Cr2O3、NiCr2O4、Al2O3与TiO2组成。合金分别在800、900℃空气中及在800℃水蒸气中的氧化增重与氧化时间近似遵循抛物线规律。水蒸气环境下温度变化对氧化速率的影响要明显高于空气氧化。

High temperature oxidation test was carried out on Inconel 740H superalloy at 700℃,800℃and 900℃in air and water vapor environment.The thermo-gravimetry,X-ray diffraction,scanning electron microscope and EDS were used to study the samples.The results show that the composition of oxide film formed by oxidation in air for long time is similar to the oxide film in water vapor for long time.The oxidation is mainly composed of Cr2O3,NiCr2O4,Al2O3and TiO2.The oxidation mass gain of the alloy at 800/900℃in air environment and water vapour oxidation mass gain at 800℃approximately obey the parabolic rule.The effect of temperature change on the oxidation rate in water vapor environment is more obvious than that in air oxidation.