为了将激光诱导击穿光谱(LIBS)应用到受热面金属材料特性的研究，选择不同晶粒度等级(7级、6级、5级和4级)的12Cr1MoV合金钢为对象，研究不同实验条件下（不同激光能量和光斑直径），12Cr1MoV晶粒度等级与激光诱导击穿光谱特性的关联性。研究结果表明，当光斑直径为206 μm时，在不同能量条件下，不管是基体元素Fe还是合金元素Cr的谱线强度，均与样品的晶粒度等级之间存在较好的关联性。分析Fe离子线与原子线比值时发现，当采用100.6 mJ激光能量、206 μm光斑直径时得到的拟合度达到0.987，优于直接根据谱线强度得到的拟合效果。

In order to apply laser induced breakdown spectroscopy (LIBS) to the study of the features of heating surface metallic materials, 12Cr1MoV steel samples with different grain sizes (class 7, 6, 5 and 4) are selected as the objects. Under different experimental conditions (both laser energy and spot diameter), the relevance between spectral characteristics and different classes of 12Cr1MoV grain size is investigated. The results show that it makes a well correlation between Fe or Cr spectral intensities and different grain size classes in different enery conditions with the spot diameter of 206 μm. It is found that in the condition of 100.6 mJ laser energy and 206 μm spot diameter, the fitting degree is 0.987 which is better than the fitting effect directly obtained by the spectral intensity, when analyse the ratio of Fe ion line and atomic line.