Original Position Statistic Distribution Analysis （OPA） and Characterization of Components in Titanium Alloy Welding Sample by Laser Induced Breakdown Spectroscopy （LIBS）
SHEN Xue-jing1, 2, GUO Fei-fei2, XU Peng2, CUI Fei-peng2, LI Xiao-peng2, LIU Jia1, 2
1. Central Iron and Steel Research Institute, Beijing 100081, China
2. NCS Testing Technology Co., Ltd., Beijing 100081, China
Abstract：Titanium alloys have been used in many fields such as aerospace, marine, biomedicine, etc. due to their high strength, good corrosion resistance, and high heat resistance. Due to the heat resistance, strength, plasticity, toughness, formability, weldability, corrosion resistance and biological phase of Ti-6Al-4V (TC4) alloy. It has become the best alloy in the titanium alloy industry. When titanium alloy is welded by laser, when a surfactant is added, weld penetration can be increased, welding efficiency is improved, and the unevenness of the weld microstructure is improved, but the content and distribution of elements in the fusion zone and weld zone may be changed. So the performance of the material may be affected. In this paper, laser-induced breakdown spectroscopy (LIBS) analysis technology is used to scan the surface of TC4 titanium alloy welding specimens to obtain multi-element composition information simultaneously. At the same time, combined with the original position statistic distribution analysis method (OPA), the composition and its distribution state of base material, fusion zone, weld composition of titanium alloy can be quickly characterized, and a new evaluation method will be provided for the selection of the active agent and the material properties of titanium alloy after welding. In this paper, two different active agents are selected to weld the TC4 titanium alloy sheet. The longitudinal section of the weld is used as the analysis surface, 320 mesh alumina sandpaper is used for surface treatment LIBSOPA system is used for composition distribution analysis. Firstly, the condition optimization experiment was carried out on the excitation spot and ablation conditions. Finally, the 200 μm excitation spot, 10 pre-ablation pulses and 10 ablation pulses were selected for the experiment; secondly, the calibration curves of C,Al, V, Fe, Si, Ti six elements were established (Si element mainly comes from the active agent), and then the area scanning of the titanium alloy welding samples was finished, and the element content and distribution state were characterized. Samples were taken from different parts of the titanium alloy welding samples, and the high-frequency infrared method was used to analyze the C element content, which verified the correctness of the LIBSOPA technology analysis C results. The distribution results of the elements Al, V, Fe, Si and Ti correspond to the microbeam X-ray fluorescence spectrometry. In this paper, LIBSOPA technology is used to characterize the composition distribution of multiple elements in the titanium alloy base metal, fusion zone and weld, which provides a new evaluation and characterization method for quickly determining the composition and distribution status titanium alloy weld.
Key words：Laser-induced breakdown spectroscopy; Original position statistic distribution analysis; Titanium alloy; Weld; Components distribution
沈学静，郭飞飞，徐 鹏，崔飞鹏，李晓鹏，刘 佳. LIBS对钛合金焊缝中成分的原位统计分布分析表征[J]. 光谱学与光谱分析, 2021, 41(12): 3869-3875.
SHEN Xue-jing, GUO Fei-fei, XU Peng, CUI Fei-peng, LI Xiao-peng, LIU Jia. Original Position Statistic Distribution Analysis （OPA） and Characterization of Components in Titanium Alloy Welding Sample by Laser Induced Breakdown Spectroscopy （LIBS）. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(12): 3869-3875.
