On the use of the transient hot-strip method for measuring the thermal conductivity of high-conducting thin bars

The thermal conductivity of thin, high-conducting ceramic bars-commonly used in mechanical tensile testing-is measured using a variant of the short transient hot-strip technique. As with similar contact transient methods, the influence from the thermal contact resistance between the sensor and the sample is accurately recorded and filtered out from the analysis-a specific advantage that enables sensitive measurements of the bulk properties of the sample material. The present concept requires sensors that are square in shape with one side having the same width as the bar to be studied. As long as this requirement is fulfilled, the particular size of the thin bar can be selected at will. This paper presents an application where the present technique is applied to study structural changes or degradation in reinforced carbon-carbon (RCC) bars exposed to thermal cycling. Simultaneously, tensile testing and monitoring of mass loss are conducted. The results indicate that the present approach may be utilized as a non-destructive quality control instrument to monitor local structural changes in RCC panels.