| Stainless steel is an alloy, which can resist the corrosion resistance of wat er vapor and acid solution. the main component of stainless steel is iron, whic h also contains Ni, Cr, Mn, Ti, Mo, C and other elements, wherein the chromi um content is generally more than 10.5%. Ni, Cr is a very important compone nt in stainless steel. Chromium element can change the properties of the corros ion resistance of stainless steel, which is a very important component in stainle ss steel. Ni element can improve the strength of stainless steel, and maintain st ainless steel with a good plasticity and toughness, further more, Ni element h ave a high resistance to acid and alkali, and have the function of rust and hea t resistance in the high temperature. The proportion of the added elements in t he stainless steel has a great influence on the performance of the stainless stee l. Therefore, in the production and application of stainless steel in the need for rapid and accurate determination of added elements, XRF is one of the importa nt means of detection. In the XRF analysis of stainless steel main elements Cr,Ni, Fe, between the elements have strong absorption enhancement effect,which is the main source of error analysis. The absorption and enhancement effect of elements in stainless steel has an important significance to improve the accura cy of analysis.The handhold instrument of IED-2000 T with high precision in the paper, which is developed by Chengdu University of technology, is used to analyze t he absorption- enhancement effect between Fe, Ni, and Cr in stainless steel. Xrays tube uses Ag target terminal window structure, using power is23kV/12?A; th e FWHM of the Si-PIN detector are 175eV(for Mn K? 5.9keV X ray) respective ly. The main achievements of the thesis:(1) This paper deduces the basic equation of characteristic fluorescence analy sis of XRF stainless steel samples. According to the element composition in stai nless steel, a series of two element combined sample and three element combination sample were prepared, which created the conditions for the experiment a nd the future research.(2) In this study, the effects of Fe-Ni, Fe-Cr and Cr-Ni on the characterist ic absorption and enhancement effects of the two elements were studied, and t he mass absorption coefficient curves and the characteristic X ray curves of dif ferent matrix were calculated. Comparing the measured curve and the theoretica l curve, the relationship between the content and the fluorescence count rate is obtained, and the calibration model of the characteristic absorption and enhanc ement effect of the two elements is established.(3) Based on the matrix effect of Fe-Ni-Cr three samples, and the model of the absorption and enhancement of the count rate established in the sample of two samples, establishing the correction equation of XRF analysis.(4) The analysis results show that the average relative error of Fe, Ni and Cr are 0.33%, 1.63% and 0.83%, respectively, using the method of the present method for Fe-Ni-Cr three samples. But the traditional empirical coefficient met hod, The average relative error of Fe, Ni and Cr is 0.132%, 2.8% and 0.52%.Compared with the traditional method, the average relative error is not much d ifference, so the analysis of this method can meet the general requirements.In this paper, an experimental method of matrix effect is discussed, and th e matrix effect correction model is simple and reliable. But because of the tim e and the little sample numbers, resulting in experimental work is not perfect, so in the future can be through the reduction of the sample preparation of gra dient and increase the prepared sample number and improve the resolution of t he instrument and the spectrum overlap processing and so on, to carrying out f urther research. |
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