High-temperature metal-carbon eutectic fixed-point cells with improved robustness

A novel metal-carbon eutectic fixed-point cell taking advantage of a hyper-eutectic porous structure to improve its robustness is proposed. This structure maintains its porous form and its shape even after melting. Investigation has revealed that the cell can withstand repeated rapid heating and cooling without breakage, and repeatability of the melting temperature comparable to conventional metal-carbon eutectic fixed point cells has been demonstrated. The applications of this technique to realizing secondary standards or transfer standards in thermometry, long cells for thermocouple calibration and large aperture cells for irradiance standards in radiometry/photometry are of particular interest.