Quantitative analysis of titanium alloys using one-point calibration laser-induced breakdown spectroscopy

Abstract

The development of real-time and on-line quantitative composition analysis is desired for the products quality improvement in the metal producing and processing industries. Accuracy is still a challenge for classical calibration-free laser-induced breakdown spectroscopic (CF-LIBS) quantitative analysis due to the influence of the inaccurate plasma temperature calculations, uncertainties associated with Einstein coefficients and imprecise efficiency of spectral detection system. In this paper, we present an improving quantitative analysis for both major and minor elements in titanium alloys using the one-point calibration LIBS (OPC-LIBS) method. In OPC-LIBS, one matrix-matched standard sample of known composition was used to synchronously correct the essential experimental and spectroscopic parameters. A Saha–Boltzmann plot covering a large energy range was used to obtain more accurate plasma temperature and electron density values. From the comparison results, the OPC-LIBS method leads to a more accurate determination of the titanium alloy composition compared with the conventional CF-LIBS approach.