基于手持式激光诱导击穿光谱的铁合金中非金属元素碳定量分析方法研究OA

Carbon is a critical factor affecting the strength,plasticity,and weldability of steel.Rapid in situ quantitative detection of carbon in steel is an important task in steel testing.In this study,a handheld laser-induced breakdown spectroscopy(LIBS)instrument was used to analyze the carbon content in iron alloy samples.A rapid on-site quantitative analysis method was established by integrating baseline correction,spectral peak fitting,and piecewise fitting.The effects of four different baseline correction methods,including least squares,linear fitting,rolling ball algorithm,and Hermite interpolation,on quantitative results were compared and optimized.Gaussian and Lorentzian methods were employed for LIBS peak fitting,with the fitted peak height and peak area used as quantitative criteria.The results showed that after linear fitting combined with Lorentzian fitting of the LIBS spectra,the calibration curve based on peak area achieved a better coefficient of determination(R2=0.9686).Based on data preprocessing,segmented fitting was applied to the optimized calibration curve,further improving the calibration curve's linearity(R2=0.9756).The established quantitative method demonstrated good repeatability and accuracy for detecting carbon in iron alloys,with the absolute error(AE)ranging from 0.041%to 0.37%and the relative error(RE)between 4.74%and 32.73%.This study preliminarily verified that handheld LIBS could achieve rapid and accurate detection of key non-metallic elements in steel materials,providing meaningful insights for expanding the application prospects of handheld LIBS instruments.