摘要
对核电站压水堆一回路用Z3CN20-09M铸造双相不锈钢进行400℃恒温加速热老化试验,持续加热时间分别为1000h和3000h,利用透射电镜(TEM)分析其在不同热老化时间下亚结构的变化,以及热老化过程对亚结构的影响。结果显示,热老化过程中显微组织形态无明显变化,为奥氏体基体上分布着不连续的岛状铁素体,但亚结构发生了明显改变。奥氏体基体在热老化初期有大量位错缠结及高密度的层错,随热老化时间的延长,基体中的位错缠结程度明显减轻,层错数量大大减少,在位错、相界及晶界上有析出物出现,铁素体相内出现调幅分解。
The substructural evolution of Z3CN20-09M duplex stainless steel after accelerated aging at 400 ℃ for 1000 h and 3000 h was studied by optical microscope and transmission electronic microscope.The results show that the microstructure of Z3CN20-09M CSS is stripped and laced ferrite which discontinuously distributes in the austenite matrix.With the increase of thermal aging time,the morphology of some ferrite changes from discontinuous island and laced shape to sharp in some areas.The density of dislocations and faults decreases obviously and there are precipitated phases in the grain boundary and the dislocation.
出处
《热加工工艺》
CSCD
北大核心
2010年第18期58-61,共4页
Hot Working Technology
关键词
铸造双相不锈钢
热老化
亚结构
位错密度
层错
cast duplex stainless steel
thermal aging
substructure
dislocation density
fault
