CAJ | 학술논문

采用宏观观察、金相观察、扫描电子显微分析、成分分析等分析方法，对燃油锅炉屏式过热器发生开裂失效原因进行了分析研究。结果表明：该管长期在高温下运行产生了蠕变现象；珠光体组织出现严重的球化现象，大量碳化物呈链状沿晶界析出；过热器管道内壁存在约371.55μm厚度的氧化层。因此，管束长期局部过热服役，致使金相组织发生改变，大大降低了材料的力学性能，从而发生蠕变开裂现象。
채용굉관관찰、금상관찰、소묘전자현미분석、성분분석등분석방법，대연유과로병식과열기발생개렬실효원인진행료분석연구。결과표명：해관장기재고온하운행산생료연변현상；주광체조직출현엄중적구화현상，대량탄화물정련상연정계석출；과열기관도내벽존재약371.55μm후도적양화층。인차，관속장기국부과열복역，치사금상조직발생개변，대대강저료재료적역학성능，종이발생연변개렬현상。
The failure reasons of a platen superheater tube of a fuel-oil boiler were studied by macroscopic observation, metallographic analysis, scanning electron microscopy ( SEM ) and energy dispersive spectroscopy ( EDS ) . The result of macroscopic observation shows that creep cracking happened to the tube after working for a long time at high temperature. The result of metallographic analysis shows that the carbide precipitated at grain boundaries. The result of scanning electron microscopy( SEM) and energy dispersive spectroscopy( EDS) show that a oxidation layer formed on the inside of the tube. The thickness of the oxidation layer was 371. 55μm. It can be concluded that long-term local overheating occurred to the tube during working, leading to microstructure change and reducing the mechanical properties of the material.