Normal Spectral Emissivity Models of Steel 304 at 800-1100 K with an Oxide Layer on the Specimen Surface

作者：Zhu, Wenjie; Shi, Deheng^*; Zhu, Zunlue; Sun, Jinfeng

来源：Transactions of the Indian Institute of Metals, 2017, 70(4): 1083-1090.

DOI：10.1007/s12666-016-0907-7

• Oxide layer
• Steel 304
• Temperature measurement
• Multispectral radiation thermometry
• Normal spectral emissivity model

This work investigated the normal spectral emissivity characteristics of Steel 304 over a temperature range from 800 to 1100 K and a wavelength range from 1.4 to 2.1 mu m. In the experiments, specimens were heated in air for 6 h at a certain temperature. Two platinum-rhodium thermocouples were symmetrically welded onto the front surface of the specimens near the measuring area for accurate monitoring of the surface temperature. The temperatures measured by the two thermocouples had an uncertainty of 1 K. The average of their readings was regarded as the temperature of the specimen surface. The radiance stemming from the specimens were measured at temperatures from 800 to 1100 K in increments of 20 K by multispectral radiation thermometry. Variation in the normal spectral emissivity with respect to wavelength and temperature was studied for different heating times. The effect of surface oxidization on the accurate prediction of the specimen surface temperature was discussed. Similar variation in the normal spectral emissivity for different heating times showed that the emissivity followed a certain rule. Nine emissivity models were examined for accuracy in the temperature prediction. The results showed that the four-parameter log-linear wavelength and line wavelength emissivity models generated best overall temperature prediction. We concluded that the effect of surface oxidization on the emissivity models of Steel 304 could be dismissed; and that the same models could be used to predict its surface temperature from 800 to 1100 K.

• 出版日期2017-5
• 单位河南师范大学