几种常用钢材的光谱发射率特性研究

发布时间：2019-02-12 22:48

【摘要】：钢是一种最基本的金属材料,在许多领域都有着广泛应用。在钢的生产和加工过程中,温度的准确测量至关重要。因为准确的温度测量不仅会影响到钢的品质和特性,而且还关系到能耗的高低。在多数的测温场合,传统的接触法测温无法凑效。目前,辐射测温技术已在金属冶炼和加工取得了广泛的应用。而辐射测温技术面临的一个难题就是材料发射率的不确定性。在工业过程中,由于受温度、氧化等因素的影响,材料的发射率往往是一个复杂的变量,这已经成为制约辐射测温技术发展的一个难题。钢的种类众多,其光谱发射率特性也不相同。本文利用基于傅里叶红外光谱仪的光谱发射率测量装置和一套反射式光谱发射率测量装置测量了五种常用的钢在不同状况下的光谱发射率,研究了表面粗糙度,合金成分以及氧化进程等因素对钢光谱发射率的影响。论文第一章介绍了钢材发射率的特点以及目前面临的问题,对国内外研究现状进行了系统的总结和分析,阐述了论文的三个研究内容。文章第二章首先简单介绍了能量对比法光谱发射率测量的基本理论知识,并对课题组搭建的基于傅立叶红外光谱仪的光谱发射率测量装置的主要组成部分、测量方法进行了简要的介绍,对测量装置的背景辐射和响应系数进行了测试。论文第三章通过对比测量六种表面处理的E235B钢氧化前后在2-15?m的光谱发射率,研究了表面粗糙度对钢在氧化前后发射率特性的影响。研究表明:表面粗糙度是影响钢光谱发射率的一个主要因素,光学粗糙度的确可以作为评估表面形貌对光谱发射率影响的一个参数,但用单一的粗糙度参数并不能完全地描述表面形貌对发射率的影响。氧化后钢样品的表面形貌发生了一些变化,表面粗糙度相比氧化前变大,光谱发射率也明显增大。光谱发射率曲线出现了明显的震荡,利用薄膜干涉理论可以解释这种现象的发生。论文第四章通过对低碳钢310,中碳钢45#和高碳钢T10在氧化前后光谱发射率的测量,探究了合金成分对钢氧化前后发射率特性的影响,结果表明:合金成份会对钢的发射率产生不同程度的影响,并且这种影响在氧化前后是不同的。对于未氧化的钢,碳含量越高,光谱发射率会越大,三种钢的发射率相差不超过0.05。氧化后三种钢的光谱发射率整体分布与氧化前大致一样,但是光谱发射率值比氧化前大。因为钢成分中的Al、Cr、Ni等成份会抑制钢氧化膜的生长,使得45#钢的光谱发射率值比310和T10钢的略大。钢表面颜色对光谱发射率也会有一定影响,氧化后310和T10钢的表面由原来的银白色变成了淡蓝色,45#钢变成了紫黄色。论文第五章利用一套反射式光谱发射率测量装置实时测量了Q235A钢从300K加热到923K过程中在1.55?m处发射率的变化情况,探究了氧化进程对钢发射率的影响,结果表明氧化进程对钢发射率有着不可忽视的影响,Q235A钢在加热过程中发射率并不是一直增大的,而是会出现一定的波动,最后利用干涉理论粗略估算了波动出现时钢氧化层的厚度。本文旨在通过对影响钢材光谱发射率各种因素的研究,总结出钢材光谱发射率的一般规律,丰富钢材的发射率数据,从而推动对不同状况下钢材的光谱发射率及其特性的进一步研究。
[Abstract]:Steel is one of the most basic metallic materials, which is widely used in many fields. The accurate measurement of temperature is critical in the production and processing of steel. Because accurate temperature measurement can not only affect the quality and characteristics of the steel, but also the energy consumption. In most cases of temperature measurement, the traditional contact method can not be used to measure the temperature. At present, the radiation temperature measurement technology has been widely used in metal smelting and processing. The problem of radiation temperature measurement is the uncertainty of the emissivity of the material. In the industrial process, due to the influence of the factors such as temperature and oxidation, the emissivity of the material is often a complex variable, which has become a difficult problem to restrict the development of the radiation temperature measurement technology. There are many kinds of steel, and its spectral emissivity is not the same. In this paper, the spectral emissivity of five commonly used steels under different conditions is measured by a spectral emissivity measuring device based on a Fourier transform infrared spectrometer and a set of reflective spectral emissivity measuring devices, and the surface roughness is studied. The influence of the factors such as the composition of the alloy and the oxidation process on the emissivity of the steel. In the first chapter, the characteristics of the emissivity of steel and the problems at present are introduced in the first chapter, and the present situation of domestic and foreign research is summarized and analyzed, and the three research contents of the paper are described. In the second chapter, the basic theoretical knowledge of the measurement of the spectral emissivity of the energy contrast method is briefly introduced, and the main components and measurement methods of the spectral emissivity measuring device based on the Fourier transform infrared spectrometer are briefly introduced. The background radiation and response coefficient of the measuring device were tested. In the third chapter, the effect of surface roughness on the emissivity of steel before and after oxidation was studied by comparing the spectral emissivity of 2-15? m before and after the oxidation of the six surface-treated E235B steel. The results show that the surface roughness is one of the main factors that affect the emissivity of the steel, and the optical roughness can be used as a parameter to evaluate the effect of the surface topography on the spectral emissivity, but the influence of the surface morphology on the emissivity can not be fully described with a single roughness parameter. The surface morphology of the steel samples after oxidation has changed, and the surface roughness becomes larger than before oxidation, and the spectral emissivity is also obviously increased. The spectral emissivity curve shows an obvious oscillation, and this phenomenon can be explained by the film interference theory. In the fourth chapter, the influence of the alloy composition on the emissivity of the steel before and after oxidation was investigated by measuring the emissivity of the low-carbon steel 310, the medium carbon steel 45 # and the high-carbon steel T10 before and after the oxidation. The results show that the alloy composition can have different influence on the emissivity of the steel. and this effect is different before and after oxidation. For unoxidized steel, the higher the carbon content, the greater the spectral emissivity, and the difference in the emissivity of the three steels is not more than 0.05. The overall distribution of the spectral emissivity of the three steels after oxidation is the same as before the oxidation, but the value of the spectral emissivity is greater than before the oxidation. Because the components of Al, Cr, Ni in the steel component can inhibit the growth of the steel oxide film, the spectral emissivity of the 45 # steel is slightly larger than that of the steel of 310 and T10. The surface color of the steel has a certain effect on the spectral emissivity, and the surface of the oxidized 310 and T10 steel is changed from the original silver white to the light blue, and the 45 # steel becomes purple yellow. In the fifth chapter, the change of the emissivity of Q235A steel from 300K to 923K is measured in real time by a set of reflective spectral emissivity measuring devices, and the effect of the oxidation process on the emissivity of steel is investigated. The results show that the oxidation process has an unnegligible effect on the emissivity of steel. The emissivity of the Q235A steel in the heating process is not always increased, but a certain fluctuation occurs, and finally, the thickness of the steel oxide layer is roughly estimated by using the interference theory. The purpose of this paper is to summarize the general rule of the spectral emissivity of the steel and enrich the emissivity data of the steel, and to further study the spectral emissivity and the characteristics of the steel under different conditions.
【学位授予单位】：河南师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG142.1

【参考文献】