Comparison of single- and multivariate calibration for determination of Si, Mn, Cr and Ni in high-alloyed stainless steel by Laser-Induced Breakdown Spectrometryтезисы доклада
Дата последнего поиска статьи во внешних источниках: 28 мая 2015 г.
Аннотация:The use of Laser-Induced Breakdown Spectroscopy (LIBS) is significantly expanded in last decade for qualitative and quantitative analysis of samples of different origin (aerosols, environmental objects, pieces of art, coating layers, composite materials, alloys etc). LIBS provides non-contact sampling by focused laser radiation. This is make possible the elimination of sample preparation and extremely short analysis time. These advantages of LIBS give an opportunity to create techniques for rapid direct analysis of steels during operation process. It is necessary to determine simultaneously impurities and doping components, but there is a numerous spectral interferences in case of high alloyed stainless steel due to extremely complex spectra of main components – iron, chromium and nickel. Therefore, the goal of this work is to eliminate matrix interference by temporal selection of LIBS signal and the use of multivariate regression.
The evolution of plume generated by laser ablation of high-alloyed stainless steel (Fe~55%, Cr~25%, Ni~15%, Mn~1,5%, Si~1%) with second and third harmonic of Nd:YAG was studied to find appropriate gating parameters for silicon determination. Different calibration approaches were compared – multivariate regression and common calibration in two spectral regions 280-300 nm and 210-232 nm. Combination of temporal selection of analytical lines (or spectral interval near to) Si I 288.16 nm, Si I 212.2 nm, Mn I 403.07 nm, Cr II 282.24 nm, Ni II 221.65 nm and mathematical selection via multivariate regression allows quantitative determination of these elements with RSD~3-5%.