The Annealing Effect on the Performance of the Standard Platinum Resistance Thermometer
DENG Xiao-long1,SUN Jian-ping2,YUE Kai1,LI Jie3,WU Xin-cai3
1. University of Science and Technology Beijing, Beijing 100083, China;
2. National Institute of Metrology, Beijing 100029, China;
3. Hebei University, Baoding Hebei 071000, China
Abstract：Annealing is the most effective means to eliminate internal stress of SPRT that is due to factors such as mechanical vibration.At the same time, it may change the internal oxidation state of platinum wire.Four SPRTs from different countries are chosen,these SPRTs are annealed at five different temperatures (600 ℃、500 ℃、450 ℃、420 ℃、350 ℃) for 4 hours to investigate their stability at room temperature after annealing.The results show that different annealing temperature can produce different effects on resistance of thermometers,equivalent to temperature changes maximum 1 mK,the water triple point resistance changed significantly in 0 to 6 hours, to keep the platinum resistance thermometer in a same thermal state can effectively improve the temperature measurement level.
邓小龙,孙建平,乐恺,李杰,武鑫财. 退火对标准铂电阻温度计性能影响的研究[J]. 计量学报, 2015, 36(1): 26-30.
DENG Xiao-long,SUN Jian-ping,YUE Kai,LI Jie,WU Xin-cai. The Annealing Effect on the Performance of the Standard Platinum Resistance Thermometer. Acta Metrologica Sinica, 2015, 36(1): 26-30.
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