METHOD OF MANUFACTURING PLATINUM RESISTANCE THERMOMETER, AND PLATINUM THERMOMETRY RESISTANCE ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide a method of manufacturing a platinum resistance thermometer capable of attaining high replicability and highly efficient use by high stability with few resistance value changes even in use at temperature area of 300-500°C or less where replicability is low due to oxidation of platinum, and to provide a method of manufacturing a platinum thermometry resistance element.;SOLUTION: The manufacturing method includes: a gas sealing process S1 for sealing purge gas G into a protective tube 3 attached with a thermosensitive part 2; a reduction process S2 for setting an internal temperature of the protective tube 3 to a temperature region under a platinum reduction state in a partial pressure of oxygen contained in a purge gas G and reducing the thermosensitive part 2 to Pt; a first oxidation process S3 for setting an internal temperature to a temperature of T_A or less to oxidize the thermosensitive part 2 into PtO₂; a second oxidation process S4 for setting the internal temperature to a temperature between T_A and T_B to change PtO₂ of the produced thermosensitive part 2 into PtO; and a sealing process S5 for adjusting a partial pressure of oxygen contained in the purge gas to seal the protective tube so that T_B becomes a maximum temperature or more in a working temperature region.;COPYRIGHT: (C)2010,JPO&INPIT