氧化皮和脱碳层对锅炉部件表面金相检测结果的影响分析及优化

Analysis and optimization of oxidation and decarburization layer on the surface of boiler parts metallographic examination results

表面金相组织分析是监测锅炉高温部件材质状况的最直接、有效的方法和手段。为了优化金相检测准确性和检测精度,通过梳理表面金相检测的劣化类型、判定依据、检测部位要求和结论评判等理论体系,结合多年积累的现场检测经验,并通过对锅炉部件进行取样,开展实验室试验来验证金属部件表面对金相检测结果的影响程度。结果显示,氧化皮和脱碳层是影响表面金相结果的主要因素。实际工作中对部件的表面打磨深度一般应控制在0.5 mm以上;部件较厚或表面氧化皮较厚时,应采用阶梯式递进开展检测,同时结合强度要求渐进式开展表面金相检测。

The microstructure of surface analysis is the most direct and effective methods and means for the boiler monitoring of high temperature components. In order to optimize the optical detection accuracy and detection accura-cy, judging degradation type, carding surface metallographic test, testing site requirements and conclusion evaluation theory system were made. Combined with field testing experience, accumulated over the years, and through the sam-pling of boiler components, the development of laboratory tests were to verify the influence of the metallographic ex-amination of the metal parts surface. The results showed that oxidation and decarburization layer are the main factors that influences the results of metallographic surface. In the actual work, the surface parts of the grinding depth should be controlled above 0.5mm; when the oxide skin or the decarbwrization layer is thick, the gradual ladder should be carried out, combined with the strength of gradual development of surface metallurgical testing.