高强度不锈钢中超低硫的不确定度评定

Evaluation of uncertainty of ultra low sulphur in high-strength stainless steel with infrared absorption method

根据实际情况及文献应用不确定度评定的理论和方法,对高强度不锈钢中超低硫的不确定度产生的原因进行分析和评定,建立不确定度评定体系和模型,确定分析结果的置信区间。本次测量高强度不锈钢中硫量测定的置信区间为:0.000 495±0.000 080。经过计算,标准物质硫的质量分数、高强度不锈钢试样的测量重复性、标准物质校准仪器的变动性以及空白值测量对不确定度的贡献大。在实际测量过程中,选用赋值准确度高的标准物质、利用标准物质校准仪器的过程、应用足够低并稳定空白值以及正确操作对准确分析高强度不锈钢中硫量至关重要。

This paper conducts an analysis and evaluation on the reasons of the uncertainty of ultra low sulphur in high-strength stainless steel by applying theory and method for uncertainty evaluation based on practice and literature review,establishes the system and mode for evaluation of uncertainty,and works out the confidence interval of research results.The confidence interval of sulphur content measurement in stainless steel in the paper is:0.000495±0.000080.After the calculation,it is found that the uncertainty is largely attributed to quality fraction of standard substance of sulphur,repeatability of measurement of high-strength stainless steel sample,variability of calibration instrument of standard substance and measurement of baseline value.In the process of actual measurement,it is critical for the precise analysis of the amount of sulphur in high-strength stainless steel to select the standard substance with high-accuracy assignment,to utilize the calibration instrument of standard substance,to apply the baseline value that is low enough and stable,and to operate correctly.