选用珠光体耐热合金钢12Cr1MoV作为研究对象，通过不同的热处理过程制备了金相组织为珠光体+铁素体、板条状回火马氏体+少量残余奥氏体、回火马氏体和回火索氏体的样品，对比分析了激光诱导击穿光谱（LIBS）的谱线强度、等离子体温度、电子密度以及Fe元素离子线和原子线谱线强度比与金相组织之间的关系。研究结果表明：回火马氏体的光谱强度最强，珠光体+铁素体和板条状回火马氏体+少量残余奥氏体的光谱强度接近，回火索氏体的光谱强度最弱；各样品的等离子体温度基本一致；回火马氏体的电子密度最大，其余样品电子密度基本一致；Fe元素离子线和原子线强度比与金相组织存在一定的关联性，说明LIBS技术具有分析锅炉受热面金相组织变化的潜在能力。

The pearlitic heat resistant steel 12Cr1MoV is chosen as the research object. Different microstructure samples are made by different heat treatment processes. The microstructures of these samples are pearlite and ferrite, lath martensite and a small amount of residual austenite, martensite and sorbite. The spectral intensity of laser-induced breakdown spectroscopy (LIBS), plasma temperature, electron density and the relation between microstructure and the ionic to atomic spectral line intensity ratio of Fe element are compared and analyzed. The experimental results show that the spectral intensity of martensite is strongest, the spectral intensity of ferrite and pearlite is almost similar to that of lath martensite and a small amount of residual austenite, the spectral intensity of sorbite is weakest. The plasma temperatures of samples are almost consistent. The electron density of martensite is the maximum and those of remaining samples are similar. There is a certain correlation between Fe ionic and atomic line intensity ratio and microstructure, which indicates that LIBS has the potential to be used as detection tool of microstructure variation of heat transfer surfaces in power plant boilers.