In-Situ Lithium Analysis In MgLi Alloys Using Laser-Induced Breakdown Spectroscopy with a Compact Chamber.

Abstract

This study explores the feasibility of in situ Lithium (Li) analysis in Magnesium-Lithium (MgLi) alloys using Laser-Induced Breakdown Spectroscopy (LIBS). It focuses on two Li emission lines: Li I 670.8 nm (resonance) and Li I 610.4 nm (non-resonance). Comparing characteristics at atmospheric and low pressures, self-reversal signatures are observed in both emission lines at atmospheric pressure, complicating the analysis. Challenges in suppressing self-reversal effect using laser energy and detection window adjustments are noted. To address this, a compact chamber (80 mm×50 mm×50 mm) with adjustable pressure (using a portable vacuum pump) is developed. Lowering the pressure significantly reduces self-reversal effect, particularly for the Li I 610.4 nm line. This makes Li I 610.4 nm more suitable for analyzing high Lithium concentrations in MgLi alloys. Using standard samples, such as LA91 (8 % Li) and LA141 (14 % Li), the study successfully obtains Li I 610.4 nm spectra with proportional Li emission intensities. Even with a commercially affordable time-integrated charge-coupled device (CCD) detection system, the results indicate the efficacy of this approach for in situ Li analysis in MgLi alloys.