Modeling the effect of surface oxidation on the normal spectral emissivity of steel 316L at 1.5 mu m over the temperatures ranging from 800 to 1100 K in air

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

来源：Infrared Physics & Technology, 2015, 71: 370-377.

DOI：10.1016/j.infrared.2015.05.012

• Steel 316L
• Normal spectral emissivity
• Oscillation
• Surface oxidization
• Oxidization layer
• Heating time

The effect of surface oxidation on the normal spectral emissivity of steel 316L has been modeled at 800-1100 K in air at 1.5 mu m. The radiance from the specimen is received by an InGaAs photodiode detector. The specimen temperature is obtained by averaging the two platinum-rhodium thermocouples, which are welded in the front surface of specimen near the measuring area viewed by the detector. The normal spectral emissivity of steel 316L specimens is measured in air over a 6-h heating period at a definite temperature. The strong oscillations of normal spectral emissivity have been observed and discussed, which are affirmed to be connected with the thickness of oxidization layer on the specimen surface, and formed by the interference effect between the radiation stemming from the oxidization layer and the radiation from the substrate. At a given temperature, the variation of normal spectral emissivity with the heating time abides by an analytical model. And at a definite heating time, the variation of normal spectral emissivity with the temperature also follows the same functional form. The uncertainty of normal spectral emissivity contributed only by the surface oxidation is about 3.7-15.0%, and the corresponding uncertainty of temperature yielded only by the surface oxidization is about 4.1-11.7 K. The conclusion is that the analytic model used here can well reproduce the behaviors of normal spectral emissivity except for the strong oscillation occurring in the initial heating period.

• 出版日期2015-7
• 单位河南师范大学