摘要
为研究马氏体耐热钢中的Laves相析出行为及对蠕变强度影响,利用透射电镜对全马氏体组织和含少量高温δ铁素体的马氏体组织中的Laves相进行观察与分析,研究不同组织中Laves的析出行为以及蠕变温度与应力对Laves相形貌和尺寸的影响。结果表明:在全马氏体组织中,观察到Laves相有两种形核机制,一种是在晶界上单独形核并长大,另一种是在毗邻M23C6碳化物处形核并长大;在含高温δ铁素体的马氏体组织中,Laves相则会优先在高温δ铁素体内形核,且温度和应力促进了Laves相的形核和长大。
The precipitation behavior and influence of Laves phase in martensitic heat resistant steel was studied by contrasting the whole martensitic microstructure and the martensitic microstructure which containing a small amount of delta ferrite. The Laves phase was observed by using a transmission electron microscope（ TEM）,and subsequent analysis is implemented in respect of the precipitation behavior of Laves phase in different microstructure and the influence of creep temperature and stress on the morphology and size of Laves phase. The results show that there are two mechanisms of the nucleation and growth for Laves phase in whole martensitic microstructure,one of which is that Laves phases occur alone on grain boundaries while the other one is that Laves phases are formed in the regions adjacent to M23C6 particles. But in martensitic which contained a few delta ferrite,the Laves phase is nucleated preferentially inside the delta ferrite. The higher creep temperature and stress can promote the nucleation and growth of Laves phase.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2015年第9期109-113,共5页
Transactions of Materials and Heat Treatment
基金
国家自然科学基金重大项目(51034011)
华能国际科研项目(HNKJ13-G16)
关键词
马氏体耐热钢
LAVES相
析出行为
Δ铁素体
Martensitic heat-resistant steel
Laves phase
Precipitation behavior
Delta ferrite
