FIG 4 - uploaded by Kaihua Zhang
Content may be subject to copyright.
Context in source publication
Context 1
... given temperatures (750, 800, 850, and 900 K) respectively. The samples were heated up to the given temperatures under the argon environment, then air was introduced for isothermal oxidation. Measurements were performed during the whole thermal oxidation process to track the evolution of the spectral band emissivity, and the results are shown in Fig. 4. When the temperature is below 750 K, all emissivity curves show linear increase trends with different initial values, thus the emisivity values at these temperatures are not shown. In general, thermal oxidation can lead to the increase of emissivity to a large extent. The oxidation speed grows faster at higher temperature. During the ...
Similar publications
The effect of vibration (50 Hz) on the formation of aluminum castings of 99.5% purity at various cooling rates was studied. It was found that the presence of vibration leads to an increase in the cooling rate of the castings. It was found that the higher the speed without vibration, the stronger the effect of increasing the speed when vibration was...
Citations
... Based on the effects of emissivity on infrared temperature measurement accuracy, Shen et al. established a model to improve the temperature measurement accuracy of unsteady temperature field [20]. Zhang et al. analyzed the spectral band emissivity of aluminum metal during oxidation [21]. Sade and Katzir used multi-band infrared fiber radiation to measure the temperature and emissivity of objects [22]. ...
... The temperature matrix T obtained in Eq. (20) is substituted into Eq. (21), and the following equation set can be obtained: ...
... The obtained α matrix is substituted into Eq. (21), and the temperature field distribution T (x, y) can be obtained. ...
Temperature is considered a critical factor in improving the quality of workpieces in the manufacturing of aluminum alloys. To improve the temperature measurement accuracy of aluminum alloys and realize on-line measurement, this paper proposes a method for measuring the temperature field of aluminum alloys with infrared radiation combined with blackbody spots calibration. Since the emissivity of aluminum alloys changes with the surface characteristics of an object, there is a certain difference between the directly measured temperature using the infrared thermal imager and the actual temperature of the aluminum alloy surface. For this purpose, a correction method of infrared radiation temperature field of aluminum alloy based on image mapping theory was established. The uniform and non-uniform temperature fields of the aluminum alloy workpiece were designed, and the temperature field of the aluminum alloy plate was reconstructed based on the image mapping theory and the blackbody spots temperature. The study reveals that accurate measurement of the temperature field of aluminum alloys can be achieved based on infrared radiation combined with blackbody spots online calibration, and the maximum error is 1.5 K. Therefore, the method is suitable for industrial applications of aluminum alloys where emissivity varies with temperature.
