Thermoelectric Effects of Cold Work in Pt/10%Rh and Pt/13%Rh Versus Pt Thermocouples
Autor: | T L Morgan, R E Bentley |
---|---|
Rok vydání: | 1984 |
Předmět: | |
Zdroj: | Metrologia. 20:61-66 |
ISSN: | 1681-7575 0026-1394 |
Popis: | We have investigated the consequences of cold work introduced in handling PtRh versus Pt thermocouples and found changes in the Seebeck coefficient of up to -40 nV/°C and errors in calibration of up to -0.4%. We show that above 200 °C recovery in the Seebeck coefficient towards its pre-cold-worked value occurred at an increasing rate with temperature but that in the PtRh leg, unlike the Pt leg, the recovery was not complete. A residual effect, attributed to PtRh, of up to -4 μV remained in thermocouple emf after recovery anneals had been applied. Recommendations are made for the handling of high-quality Pt-based thermocouples. |
Databáze: | OpenAIRE |
Externí odkaz: |