The Device Establishment And Measurement Of Melt Spectral Emissivity

Melt spectral emissivity has a broad application background,not only for the melt true temperature measurement,heat transfer analysis,preparation of process optimization is of great significance,but also can give the melt structure analysis of usefurl information and can promote the understanding and development of the melt.China's manned space“station”and“no container material experiment ark”planned melt spectral emissivity measurement function.Based on the emissivity definition which is the ratio of sample spectral radiant intensity and the standard blackbody radiation intensity under the same temperature,using the same optical path conditions,the same temperature measuring melt and blackbody radiation spectrum intensity respectively,and then calculate the ratio to obtain the melt material spectral emissivity.Measurement device of melt spectral emissivity was built based on the principle,including sample heating furnace,blackbodyfurnacelightpathsystemandradiationmeasurement system.Sample heating furnace uses infrared heating tubes this untraditional heating mode,in this method,infrared heating tubes and samples were placed in the oval reflector focus,oval layout using focus convergence characteristics of the infrared tubes heat concentrated light samples.Using three tubes arranged around the sample,is in the shape of an equilateral triangle with three tubes make sample surface is heated in an all-around way.Samples of infrared radiation heating and heating efficiency can be improved more than a few times.Heating than laser heating tubes,on the another hand,the cost is low,and save space,with no secondary pollution.Through the linearity test of radiation measurement system and fitting residual error distribution,we get the biggest nonlinear error is 0.4039%,conforming to the requirements of the linearity of system.solid nickel material emissivity in2.5?m²5?m wavelength range,measure and analyze the changing with the temperature and wavelength.In2.5?m¹1?m,its spectral emissivity with the increase of wavelength is on the decline.After 11¹6?m gradually smooth,in 305?to1000?,as the temperature increases emissivity rises.The uncertainty analysis of the results,the biggest uncertainty is 5%,verifying the device reliability and accuracy.Using building device and air suspension device respectively measured the Sn metal melt,MgO and Al₂O₃ of metal oxide melt spectral emissivity.Results show that the spectral emissivity of Sn metal melt with the increase of wavelength increases,as the temperature increases its value also increased.Spectral emissivity of MgO melt at350 nm²200 nm wavelength analysis found that the change rule of MgO melt at 350nm⁹80 nm spectral emissivity is on the decline,with the increase of wavelength at980 nm²200 nm with the increase of the wavelength is parabolic,its first rise to maximum and then decreased.At 2600?,2700?,2800?,under the three temperature points changing with the temperature is350⁹80 nm with the temperature rising and falling,in 980 nm to 2200 nm,fluctuated with the temperature,spectral emissivity under 2700?is maximum.The emissivity of Al₂O₃ melt change with the wavelength rule with MgO melt is the same wavelength change rule.In the 350nm⁹80nm decreased,with the increase of wavelength.At 980nm²200nm with the wavelength change is in the shape of parabola to rise to the fullest then fall first.Its in2400?,2500?,2600?,2700?,2800?five point temperature,with the temperature change rule for the 350nm⁹80nm with the temperature rising downward trend;In 980nm²200nm wavelength range,spectral emissivity under 2700?is maximum.In this paper we develop the spectral emissivity measurement device of metallic melts,Through the device and air suspension system measured the Sn melt metal and metal oxide MgO?Al₂O₃ spectral emissivity.Because of the melt spectral radiation measurement data is less,the melt spectral emissivity data can provide the ground reference data for future space"container"in this article.