What is the commonly used thermocouple materials _ instrument

Commonly used thermocouple indexing, hot thermocouple material and electrode material, using temperature range ( ℃) The positive negative platinum rhodium (S Rhodium content 10%) Pure platinum 0 1400 R platinum rhodium ( Rhodium content 13%) Pure platinum 0 Platinum rhodium (1400 B Rhodium content 30%) Platinum rhodium ( Rhodium content 6%) 0 - Nickel chromium nickel silicon - 1400 K 200 - + 1000 T pure copper copper and nickel 200 - + J iron copper and nickel - 300 200 - + N nickel chrome silicon nickel silicon - 600 200 - Nickel chromium copper nickel - + 1200 E 200 - + 700 in theory, any two different conductors ( Or a semiconductor) Can be made into thermocouple, but as a practical temperature measurement component, is various to the requirement of it. In order to guarantee the reliability of engineering, as well as the measuring accuracy of enough, not all materials can form a thermocouple, generally electrode materials of thermocouple, basic requirements are: ( 1) , within the scope of the temperature measurement, thermoelectric properties of stability, not change with time, there is plenty of physical and chemical stability, less susceptible to corrosion and oxidation; （ 2) Electrodes, thermocouple temperature coefficient of resistance small, high electrical conductivity, specific heat; （ 3) , the temperature of thermoelectric ShiYao big and between thermoelectric potential and temperature is linear or close to linear single valued function relation; （ 4) , electrode material of thermocouple replication is good, high mechanical strength, simple manufacturing process, the price is cheap.