[Multi-Element Detection in Molten Steel with Laser-Induced Breakdown Spectroscopy]

Area of Science:

• Metallurgical analysis
• Spectroscopy
• Materials science

Background:

• On-line elemental analysis is critical for quality control in the iron and steel industry.
• Laser Induced Breakdown Spectroscopy (LIBS) offers a promising technique for in-situ molten steel analysis.

Purpose of the Study:

• To develop and validate a laboratory-based LIBS system for the on-line detection of elemental composition in molten steel.
• To assess the system's performance in terms of detection limits and calibration accuracy for key elements.

Main Methods:

• A LIBS system was constructed using a Q-switched Nd:YAG laser, high-frequency induction furnace, and a UV spectrometer.
• Deep-UV detector coating and solarization-resistant fibers were employed for enhanced spectral signal collection.
• Calibration curves were generated for Carbon (C), Sulfur (S), Manganese (Mn), and Chromium (Cr) to determine detection limits.

Main Results:

• The LIBS system successfully detected multiple elements in molten steel.
• Achieved limits of detection were 169 μg·g⁻¹ for C, 15 μg·g⁻¹ for S, 58.9 μg·g⁻¹ for Mn, and 210 μg·g⁻¹ for Cr.
• Calibration curves exhibited R-squares greater than 0.96, indicating high accuracy, with optimal calibration dependent on element-specific delay conditions.

Conclusions:

• The developed LIBS system demonstrates effective on-line elemental detection capabilities for molten steel.
• The system's sensitivity and accuracy are suitable for quality control applications in the iron and steel industry.
• Optimizing spectral acquisition parameters, such as delay time, is essential for accurate multi-element analysis.