N type thermocouple what are the advantages and disadvantages compared with k type thermocouple _ instrument1

N type thermocouple n type thermocouple have the advantages of high temperature oxidation resistance is strong, long term stability. K type thermocouple nickel chromium anode preferential oxidation caused by cr, si element in the alloy composition is uneven and thermoelectric drift, cr, si content in n type thermocouple, nickel-chromium alloy oxidation patterns by internal oxidation into external oxidation, the oxidation reaction on the surface only; Short-term thermal cycling stability at low temperature, and inhibit the magnetic change; 。 - Radiation resistant ability. N type thermocouple is cancelled easy disintegration of k type thermocouple elements mn, co, further strengthen ability to resist neutron irradiation; , within the range of 400 ~ 1300 ℃, the thermoelectric properties of n type thermocouple linear than k type. N type thermocouple material is harder than k type thermocouple, the more difficult processing; The price is relatively expensive. The thermal expansion coefficient of n type thermocouple 15% lower than stainless steel, so the outer casing of n type thermocouple shall adopt the nicrsi/nisi alloy; In - 200 ~ 400 ℃ within the scope of nonlinear error is bigger.