真空汞固定点黑体辐射源的设计与研制

介绍了中国计量科学研究院研制的真空汞固定点黑体辐射源的结构、工作原理、性能测试结果和不确定度分析。真空汞固定点黑体辐射源灌注的是纯度为99.9999%的高纯汞,黑体空腔开口直径为25 mm,空腔内径为28 mm,深度为260 mm,表面喷涂了NEXTEL 811-21高发射率涂层,采用基于蒙特卡罗黑体发射率仿真计算的方法,计算了黑体空腔在波长为8~14μm的发射率,结果优于0.9999;在真空环境下,测试了真空汞固定点黑体辐射源的温坪曲线和重复性等主要技术指标,结果表明真空汞固定点黑体辐射源温坪稳定性优于2 mK,多次重复性优于1 mK;分析了真空汞固定点黑体辐射源的不确定度来源,其合成标准不确定度为16 mK。

Design and Development of Vacuum Mercury Fixed PointBlackbody Radiation Source

The structure, working principle, performance test results and uncertainty analysis of the vacuum mercury fixed point blackbody radiation source developed by NIM, China, were introduced. The perfusion metal of the vacuum mercury fixed point blackbody was high purity mercury with a purity of 99.9999%. The opening diameter of the blackbody cavity is 25 mm, the inner diameter of the cavity is 28 mm, the depth is 260mm, and the surface is coated with high emissivity coating from NEXTEL 811-21. The Monte Carlo calculation method was used to calculate the blackbody emissivity at the wavelength of 8~14μm. The emissivity is higher than 0.9999. In the vacuum environment, the main technical indicators such as the temperature curve and repeatability of the temperature of the mercury fixed point blackbody were tested. The results show that the temperature stability of the vacuum mercury fixed point blackbody is better than 2mK, and the repeatability is better than 1mK. The uncertainty source of the vacuum mercury fixed point blackbody is analyzed, the synthetic standard uncertainty is better than 16mK.