主汽阀阀杆GH901断裂分析  

Fracture Analysis on Stem GH901 of Main Steam Valve

作　　者：何朋非 谢亿[1,2] 屈国民[1,2] 

机构地区：[1]湖南省湘电锅炉压力容器检验中心有限公司,湖南长沙410004 [2]国网湖南省电力公司电力科学研究院,湖南长沙410007

出　　处：《热加工工艺》2015年第22期232-234,共3页Hot Working Technology

摘　　要：通过宏观形貌观察、力学性能测试、化学成分分析、金相组织观察和扫描电镜等试验方法,对某火力发电机组主汽阀阀杆的断裂原因进行分析。结果表明,母材中存在的大块状一次碳化物和强化相导致了材料力学性能的下降,尤其是屈服强度的下降是导致阀杆断裂的主要原因。该阀杆的断裂机制为疲劳脆性断裂。The reason for main steam valve stem of one generator unit was analyzed by macro-morphology, mechanical test, chemical composition analysis, microstructure observation and SEM-EDS methods. The results show that massive phases primary carbide in matrix and enhanced particles lead to the mechanical properties decrease sharply, especially, the decrease of the yield strength is the main reason for the fracture of valve stem. The fracture mechanism of the stem is fatigue brittle rupture.

关 键 词：一次碳化物 疲劳断裂 屈服强度 GH901 

分 类 号：TG113.2[金属学及工艺—物理冶金]