熔融过程中升温和降温对Al特征谱线的影响

为了解决LIBS技术应用于冶金过程成分分析时,温度变化导致测量精度低,重复性差的问题,就温度变化对等离子体的影响进行研究.以Al元素为研究对象,对比分析不同温度下的光谱强度、等离子体电子温度和电子密度,总结了温度上升和下降时光谱强度和等离子体特征参数的变化规律.结果表明,Al元素特征谱线强度随温度上升呈增大趋势,在70...

Effect of Heating and Cooling on the Characteristic Lines of Al During Melting

In order to solve the problem of low accuracy and poor repeatability caused by temperature change when LIBS technology is applied to the analysis of metallurgical process composition, the influence of temperature change on plasma is studied in this paper. The results show that the intensity of the characteristic lines of Al increases with the increase of temperature and reaches saturation at 700 ℃. When the temperature rises to 700, 500 and 200 ℃, Al I increases When the sample temperature is 700 ℃, the plasma electron temperature rises to 13122 K, and the electron density increases to 4.65×1016 cm-3 respectively. In the first stage, the sample stops heating and naturally cools down, and the plasma parameters drop rapidly with the sample temperature; in the second stage, when the sample temperature drops to about 660 ℃, the spectral intensity decreases slowly and becomes stable. At this time, the plasma electron The temperature was stable at about 16 000 K, and the electron density was 7.6×1016 cm-3; in the third stage, the plasma characteristic parameters continued to decrease until the sample temperature dropped to room temperature. When LIBS technology is applied to the detection of molten metal components, the best measurement point can be obtained by controlling the sample temperature, there by improving the detection accuracy of LIBS technology.