Determination of Emissivity of Brass Alloy using Infrared Thermographic Technique

Abstract

This paper presents the experimental determination of the dependence of emissivity of brass on surface roughness and temperature. The investigation was conducted using the infrared thermographic technique on brass alloy C27200 workpieces with different degrees of surface roughness, during the continuous cooling process. The results obtained showed that the emissivity of the chosen brass alloy increases with greater surface roughness and decreases during the cooling process, its value ranging from 0.07 to 0.19. It was concluded that surface roughness has a greater influence on the increase of the emissivity at higher temperatures, which can be seen in the three-dimensional infrared images. Multiple regression analysis confirmed a strong correlation between the examined parameters and the emissivity, and an original multiple regression model was determined.

An accurate instrument for emissivity measurements by direct and indirect methods

“…Although the comparison could not be undertaken under identical measurement conditions, such as the temperature, wavelength, measurement environment, and surface condition, this comparison can offer a straightforward evaluation of our instrument. Our emissivity measurements of these materials generally agree with published measurements of stainless steel [28], aluminium alloy [29], and HiE-Coat 840M paint within the literature [30]. This, therefore, validates our results and instrument's approach to emissivity measurements.…”

“…To evaluate the performance of our instrument, five sets of samples were measured, including rough SS303, rough Al6082, polished SS304, polished Al6082, and HiE-Coat 840M paint on an Al6082 substrate. These samples can represent materials ranging from low-emissivity values to high-emissivity values over the spectral range of 2.1 to 2.5 µm, according to previously published studies [28][29][30]. Samples were heated to the measurement temperatures, ranging from 200 °C to 450 °C, in sequential steps of 50 °C.…”

Multi-verse optimizer for thermal error modeling approach of spindle system based on thermal image

“…The temperature field data of the spindle system were recorded by the Fluke TiS50 thermal imaging camera. According to Abdulshahed et al 17 and Lanc et al, 18 the emissivity of the thermal imaging camera was set to 0.95. Its value and other experimental parameters are set in Table 1.…”

Desenvolvimento E Comparação De Métodos De Medição Experimental Da Emissividade: Aplicação a Superfícies De Estruturas De Flare Offshore

“…Figura 2.13: Medição de Emissividade com Termopar e Termômetro de Infravermelho (elaboração própria) Outro protocolo experimental também comumente utilizado envolve a utilização de um corpo de emissividade conhecida, por exemplo um corpo negro. Um exemplo desse tipo de experimento pode ser visto em (21), onde a superfície desconhecida e a conhecida são colocadas num forno fechado e aquecidas até o equilíbrio térmico. O equipamento é inicialmente utilizado no corpo de emissividade conhecida e sua temperatura é determinada.…”