Under standard operating conditions, the emissivity of structural alloys used for various components of nuclear reactors may evolve, affecting the heat transfer of the systems. In this study, mid-infrared emissivities of several reactor structural alloys were measured before and after exposure to environments relevant to next-generation reactors. We evaluated nickel-based alloys Haynes 230 and Inconel 617 exposed to helium gas at 1000 °C, nickel-based Hastelloy N and iron-based 316 stainless steel exposed to molten salts at 750–850 °C, 316 stainless steel exposed to liquid sodium at 650 °C, and 316 stainless steel and Haynes 230 exposed to supercritical CO₂ at 650 °C. Emissivity was measured via emissive and reflective techniques using a Fourier transform infrared (FTIR) spectrometer. Large increases in emissivity are observed for alloys exposed to oxidizing environments, while only minor differences were observed in other exposure conditions.

在标准运行条件下，用于核反应堆各个组件的结构合金的发射率可能会发生变化，从而影响系统的热传递。在这项研究中，在暴露于与下一代反应堆相关的环境之前和之后，测量了几种反应堆结构合金的中红外发射率。我们评估了暴露于1000°C的氦气中的镍基合金Haynes 230和Inconel 617，暴露于750-850°C的熔融盐中的镍基Hastelloy N和铁基316不锈钢，暴露于液态钠中的316不锈钢在650°C下，以及316不锈钢和Haynes 230暴露于超临界CO ₂在650°C下。使用傅立叶变换红外（FTIR）光谱仪通过发射和反射技术测量发射率。对于暴露在氧化环境中的合金，观察到发射率大大提高，而在其他暴露条件下仅观察到很小的差异。