Continuous High-Temperature Thermoelectric Power Monitoring of Thermal Embrittlement

Thermal embrittlement is a key concern for the structural integrity of engineering components. Monitoring thermal embrittlement may indicate susceptibility to crack initiation and growth and therefore act as a damage precursor. In this study the correlation between thermoelectric power (also known as the Seebeck Coefficient) and the hardness of thermally aged 2507 super duplex stainless steel was demonstrated, showing the suitability of using thermoelectric power as a proxy measurement for embrittlement. This article presents a continuous high-temperature thermoelectric power monitoring system that is suitable for installation on large engineering assets. Using temperature gradients in the sample of < 6.5 °C a measurement standard deviation of 5.8 nV/°C was possible, which was sufficient to monitor the ~ 850 nV/°C increase in thermoelectric power that occurred in this study.