| As an important metal,the copper has been widely used in today's social production.In recent years,with the improvement of the manufacturing,the quality of materials has become more specific in various industries.Therefore,the nature of the single cooper metal cannot meet the needs of different professions.The copper alloy has been fabricated.The copper alloys always consist of the cooper and other disparate metals.According to the different doped metals,the cooper alloys have different properties.Temperature is an important parameter in the process of metal smelting and processing.The most important factor in industrial process to obtain high performance alloy materials is accurate measurement and temperature control.In the process of metal smelting,because the metal is usually in motion,the temperature of the target is measured by the radiation thermometer.However,the accuracy of radiation measurement is largely subject to emissivity.The emissivity is the thermal property parameter of the material,and always varies with temperature,wavelength and doping.In order to improve the quality of copper smelting,it is urgent to measure the emissivity accurately.In this paper,the emissivity of four different copper alloys was roundly measured and investigated by using the self-built emissivity measurement device.The first chapter introduces the current research of domestic and foreign scholars on emissivity,and expounds the existing problems,which indicates the purpose of this paper.The basic principle of infrared radiation and the commonly used infrared radiation measuring instrument are introduced in the second chapter.Focusing on the structure of the FT-IR emissivity measurement device built by the laboratory,the structure is explained by illustration,and the measurement principle and calculation method of this experiment are explained.The next chapter explores the effects of the surface roughness,temperature and wavelength on the distribution of the emissivity by measuring four copper samples with different surface roughness.The emissivity of the four samples in the temperature range 473K-973 K and wavelength range 3-20?mare obtained.The data show that temperature and wavelength have an influence on emissivity,and the effects of both are closely related.The study also shows that surface roughness as a parameter has a significant influence on the emissivity.As the roughness increases,the emissivity of the sample also becomes larger,which is consistent with four copper samples.In order to further explain the relationship between surface roughness and material emissivity,Agababov proposes a roughness formula.The empirical data are verified by the roughness formula and good results are obtained.So as to acquire a more matching result,the formula is modified.In the fourth chapter,the influences of different doped metals on the emissivity before and after oxidation are investigated.The results show that the spectral emissivity of three kinds of copper alloys is basically consistent at different wavelength.Under the condition of oxidation,the emissivity of three copper samples changed significantly because of the formation of surface oxidation film and presented an increasing trend.But the oxidation processes of three copper alloys are not consistent.The oxidation of tungsten copper is most intense.The situation happens because of the different kinds of composition of three copper alloys,as well as the ingredient or thickness of the oxide film.However,the oxide film causes the radiation of samples transmitted through reflection and film interference,which results in the distribution difference of three kinds of copper alloys.The last chapter recommends the influence of the direction on the emissivity of the copper samples by a set of self-constructed emissivity measuring device.The emissivity of the copper sample in 573 K at the wavelength range of 3-20?mand the range of angle 0°-80° has been measured in the experiment.The results testify the influence of the direction on the spectral emissivity of material. |
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