国家温度副基准铟凝固点与国家基准的比对评述

Comments on interlaboratory comparison between national secondary standard and primary standard for temperature on indium freezing point

铟凝固点是90国际温标(ITS-90)重要的定义固定点之一,为验证中国测试技术研究院建立保存的国家温度副基准装置复现铟凝固点热力学温度的技术水平,于2018年与中国计量科学研究院的国家温度基准装置开展铟凝固点的比对。此次比对采用标准铂电阻温度计作为传递标准。传递标准分别在副基准装置和基准装置的铟凝固点中至少3个不同温坪上进行测量,并根据ITS-90规定对测量数据进行修正,计算电阻比W,将多次测量的平均值W作为实验结果。通过归一化偏差En值对测量结果的一致性进行评判,比对结果表明铟凝固点副基准与基准在0.1 mK内相一致。

Indium freezing point is one of the important fixed points in ITS-90 international temperature scale.In 2018,the interlaboratory comparison was carried out between National Institute of Metrology(NIM)and National Institute of Measurement and Testing Technology(NIMTT)on the indium freezing point(In FP)to verify the technical level of secondary standard.The SPRTs are as the artifacts by reference to the international comparison.Traveling SPRT was calibrated at least 3 plateau at the freezing point of indium of the primary standard and the secondary standard.According to the ITS-90,calibration data was corrected and the value of W was calculated.Calibration results supplied in W,where W is the mean resistance ratio from calibrations at In.The consistency of measurement results is evaluated by normalized deviation En.The comparison results show that indium freezing point secondary standard is consistent with the primary standard within 0.1 mK.