核用锆合金管氧化过程中光谱发射率特性研究

Study on spectral emissivity characteristics of zirconium alloy tubes for nuclear applications during oxidation

发射率在锆合金管非接触测温的准确性和失水事故情况下的传热分析上具有重要意义。本文采集了SZA4、SZA6和ZIRLO 3种锆合金在400,500,600℃下氧化100min过程中4~12μm内的光谱发射率数据,分析了温度、氧化膜厚度和合金组分对材料光谱发射率特性的影响规律。结果表明,3种锆合金在氧化过程中发射率变化趋势基本相同,但组分差异导致在发射率的数值和振荡特性上略有差别。通过建立薄膜干涉模型,解释了光谱发射率在波长方向上的振荡现象,并结合振荡极值与干涉效应原理计算了合金表面氧化膜厚度,在0.6~8μm范围内测量精度达到±0.3μm。

Emissivity is of great significance in the accuracy of non-contact temperature measurement of zirconium alloy tubes and the analysis of heat transfer in the case of water loss accidents.The spectral emissivity data of three zirconium alloys of SZA4,SZA6 and ZIRLO are collected within 4~12μm during 100 min of oxidation at 400,500 and 600℃,and the effect rule of temperature,oxidation film thickness and alloy components on the spectral emissivity properties of material are analyzed.The results show that the emissivity change trends of the three alloys are basically the same during the oxidation process,but the difference in components leads to slight differences in emissivity values and oscillation characteristics.The oscillation phenomenon of spectral emissivity in the wavelength direction is explained by establishing thin-film interference model,and the thickness of the oxide film on the surface of the alloys is calculated by combining the principles of oscillation extremes and interference effects,and the measurement precision of±0.3μm is achieved in the range of 0.6~8μm.