论文部分内容阅读
采用SEM、TEM及高温蠕变测试等实验方法,研究了某电厂锅炉四级过热器出口用T122管材服役前和在585~610℃服役56000 h后的组织和力学性能。结果表明:经过长时间高温服役后,T122管材的板条马氏体组织索氏体化严重,析出相聚集、长大明显,力学性能也出现较大程度下降,高温蠕变曲线及Larson-Miller参数预示服役后的管材寿命急剧缩短;考虑到T122管材服役过程中组织劣化严重,剩余服役寿命的预测并不能完全依赖于有限时间内的高温蠕变试验。
The microstructures and mechanical properties of T122 pipe before the exit of the fourth stage superheater of a power plant and 56000 h of service at 585 ~ 610 ℃ were studied by means of SEM, TEM and high temperature creep test. The results show that the lath martensitic structure of T122 pipe is seriously sorbed after prolonged high temperature service, and the precipitated phases gather and grow up obviously. The mechanical properties also decrease to a great extent. The high temperature creep curve and Larson-Miller The parameters indicate that the service life of the pipe will be drastically shortened. Considering the serious deterioration of the T122 pipe during service, the prediction of the remaining service life does not depend entirely on the high temperature creep test within a limited time.