【摘 要】
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A technique is described for the dynamic measurement of selected thermophysical properties of electrically conducting solids in the temperature range from 1100 K to the melting point. Based on rapid resistive self-heating of the specimen from room tempera
【机 构】
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DepartmentofAutomationMeasurementandControl,HarbinInstituteofTechnology,Harbin150001
【出 处】
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ChineseOpticsLetters
论文部分内容阅读
A technique is described for the dynamic measurement of selected thermophysical properties of electrically conducting solids in the temperature range from 1100 K to the melting point. Based on rapid resistive self-heating of the specimen from room temperature to any desired high temperature in several seconds by the passage of an electical current pulse through it, this technique measures the pertinent quantities such as current, voltage, randiance temperature, with sub-millisecond time resolution. The pulse-heating technique is applied to strip specimens. The radiance temperature is measured by high-speed pyrometry, normal spectral emissivity of the strips is measured by integrating sphere reflectometry. The normal spectral emissivity results are used to compute the true temperature of the specimens. The heat capacity, electrical resistivity, total hemispherical emissivity are evaluated in the temperature range from 1100 K to the melting point.
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