机械工程材料
MATERIALS FOR MECHAMICAL ENGINEERIVG DOI:10.11973/jxgccl201603024
月Vol.40No.3Mar.2016
2016年3月第40卷第3期
汽轮机高温叶片用3325YC1钢中析出相的
热力学计算及钢的成分优化
范华，王天剑
（东方汽轮机有限公司材料研究中心，长寿命高温材料国家重点实验室，德阳618000）
摘要：利用热力学计算软件Thermo-Calc计算出不同温度下3325YC1钢中M2:C，和M,B析出相的含量，以及铬、钨、钼元素含量对这两种相析出温度和析出量的影响；在此基础上通过降低铬、钨、硼含量对钢的成分进行调整，并对成分调整前后钢的高温拉伸、疲劳和持久性能进行了对比试验。结果表明：铬是M3Cs和M,B相的主要形成元素，增加铬含量对这两种相的析出量没有影响；钨是M.B的主要形成元素，随着钨含量增加，M,B的析出量增加，但析出温度没有变化；硼含量增加能明显提高CrB和M,B相的析出量，但不影响它们的析出温度；钢的成分调整后基本不会影响它的高温瞬时拉伸性能和疲劳性能，其在62o℃、10万h的Larson-Miller外推持久断裂强度仍高于100MPa。
关键调：汽轮机；高温叶片；析出相；热力学计算
中图分类号：TB31
文献标志码：A
文章编号：1000-3738(2016)03-0097-05
ThermodynamicCalculationforPrecipitatedPhasesin3325YC1SteelUsed
forHighTemperatureBlade ofSteamTurbine andComposition
OptimizingfortheSteel FAN Hua, WANG Tian-jian
(Material Research Center, Dong Fang Steam Turbine Corporation, State Key Laboratory of
Long-Life High TemperatureMaterial,Deyang 6180o0,China)
Abstract : The contents of precipitated phases Mz, C, and M, B in 3325YC1 steel at different temperature were obtained by Thermo-Cale software, as well as the effects of Cr, W and Mo contents on precipitation temperature and content of the precipitated phases. Based on the above, the chemical composition of the steel was adjusted by decreasing the contents of Cr, W and B elements, and the comparative high temperature properties like tensile. fatigue and rupture tests for 3325 YC1 steel with/without adjusting were carried out. The results show that Cr is the main element to form M2, Cs and Cr; B, but adding Cr content has no effects on precipitation contents of the two precipitated phases. W is the main element to form M, B, with the increase of W content, the precipitation content raised, but the precipitation temperature is not affected. B can not change the precipitation temperature of Cr: B and M, B, but can obviously increase their precipitation contents. The high temperature tensile and fatigue properties of 3325YC1 steel with adjusting has not affected basically, and 100 000 hour creep rupture stress at 620 *C is still higher than 1oo MPa predicted by Larson-Miller parameter method.
Key words: steam turbine; high temperature blade; precipitated phase; thermodynamic calculation
0引言
随着我国对煤炭资源利用效率以及对火力发收稿日期：2015-03-17；修订日期：2016-01-19
作者简介：范华（1964一），男，四川泸州人，高级工程师
电厂节能减排要求的提高，提高燃煤发电机组的热效率成为火力发电领域最重要的研究热点之一，而提高汽轮机的进汽初温是提高发电机组热效率的最有效方法之一。汽轮机进汽温度从亚临界的538℃到超超临界的620℃，提高了近80℃，
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