Descriptions of double platinum and rhodium(platinum and rho
This thermocouple electromotive force is too little in room temperature to use compensation lead in the measurement, can ignore the influence of reference terminal temperature changing. The double platinum rhodium’s long-term use temperature is 1600℃, short-term use temperature is 1800℃.Platinum and rhodium6’melting point is 1820℃,which can restrain machine use the upper temperature limit. And the high sensitivity of the display instrument should be equipped due to the little electromotive force rate of the double platinum and rhodium thermocouple. B type thermocouple can be used in oxidation and neutral atmosphere as well as in vacuum environment for short time. B type thermocouple’s life is 10-20 times longer than R S type thermocouple even in reducing atmosphere. Owing to the R﹠S type thermocouple positive to negative diffusion phenomenon will occur in high temperature, and causing thermocouple deterioration.. To prevent the occurrence of these phenomena, add rhodium in platinum to make platinum and rhodium alloy, which can no only improve heat resistance but also enhance thermoelectric power rate of alloy to platinum. The electromotive force of platinum and rhodium alloy to platinum will increase sharply when the rhodium content is less than 20%, once exceeds this value and with the increase of the rhodium content, electromotive force change little, the thermocouple harden significantly and process difficulty .Therefore the rhodium content of this series alloy couldn’t exceed 40%(weight ratio).
High Temperature Vacuum furnace
Sliding tube furnace
High temperature high pressure tube furnace
Large Multi station tubular furnace