Hastelloy C-276合金Σ3晶界和Σ9晶界随着退火时间的演变规律

The influence of annealing time on Σ3 boundary and Σ9 boundary evolutions in Hastelloy C-276

摘要:

Hastelloy C-276合金经小变形量冷轧后进行1100℃不同时间的退火处理。采用EBSD技术对Σ3和Σ9晶界比例进行统计,同时采用五参数法对Σ3和Σ9晶界面分布进行分析。结果表明,Σ3晶界随着退火时间的延长更加接近于标准重合点阵晶界取向,而其晶界面更加接近于低能量的{111}晶界面。这一结果符合晶界“微调”机制。Σ9晶界面分布则越来越集中在[110]晶带。而偏差较大的Σ9晶界比例增加,是由于非共格Σ3比例的增加导致的。

Abstract:

Hastelloy C-276 was subjected to low strain deformation and annealed at 1100°C for different times. The Σ3 and Σ9 boundary percentages and grain boundary plane distributions were characterized by electron back-scatter diffraction (EBSD) and the five-parameter analysis method. The results shown that the Σ3 boundary was evolving towards a more exact coincident-site lattice (CSL) misorientation and the Σ3 boundary plane was more close to low surface energy plane {111} with extended annealing time. This is consistent with fine tuning mechanism. While the population of incoherent Σ3 boundary was increasing, the proportion of Σ9 boundary with larger deviations would be increasing. And the distributions of grain boundary density planes forΣ9 boundary were more intensive on the whole [110] zone.