Laser Ablation-Inductively Coupled Plasma-Mass Spectrometer:A Quantification Strategy Based on Two Reference Materialsand Bulk Normalization as 100% (wt) / 分析化学

Quantitative calibration strategy as an essential issue in laser ablation ICP-MS plays an important role for the guarantee of analytical accuracy.In this study, uncertainties of reference values in current available glass certified reference materials (NIST, MPI-DING and USGS) as well as the matrix effect among them were systematically evaluated.The results illustrated that NIST610 was better than other reference materials from aspect of reference value uncertainty.The matrix effect among NIST, MPI-DING and USGS reference materials was insignificant under our experimental conditions.A quantification strategy based on two reference materials (NIST610 and StHs6/80-G) and normalization to 100% (w/w) was proposed to avoid the insufficiency of single reference material strategy, which suffered the very low content and large uncertainty for some elements.The comparision of ML3B-G results obtained from three quantification strategies (single reference material NIST610, single reference material StHs6/80-G and two refterence materials) illustrated that the proposed strategy improved the analytical accuracy.Three reference materials (BCR-2G, CGSG-2 and KL-2G) were quantified with the proposed strategy, and almost all data matched well with reference value, meanwhile the data reported here could supplement the reference value database.

Characterization of Inclusion Type in Steel by Laser-Induced Breakdown Spectroscopy / 分析化学

ScanningElectronMicroscopy/EnergyDispersionSpectrum(SEM/EDS),ElectronProbe Microanalysis ( EPMA ) and Optical Microscopy ( OM ) are the traditional methods for inclusion type identifying at present. The disadvantages such as inconvenient sample preprocessing, low sensitivity and time consuming limited their application. Laser-Induced Breakdown Spectroscopy ( LIBS) is not only performing in bulk analysis field but also in elemental distribution and depth profile information field, so it causes great concern in material science. In this paper, 34CrNiMo6 steel and heavy railway steel samples were analyzed by LIBS in scanning mode to characterize the inclusion type. For 34CrNiMo6 steel, 2D intensity distribution and channel combination revealed the spectra line intensity of Mn and S were abnormal high simultaneously at some region, which indicated there were some MnS inclusion existed in these samples. And for heavy railway steel, 2D distribution and channel combination revealed the spectra line intensity of Si, Ca, Mg and Al were abnormal high simultaneously at some region, showed the existence of Si-Al-Ca-Mg inclusion in these samples. The SEM/EDS analysis result of above-mentioned samples showed agreed well with LIBS.