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采用电子背散射衍射(Electron-back scatter diffraction,EBSD)技术对比研究了小形变冷轧(厚度减缩量6%)304不锈钢经低温退火和高温退火后的晶界特征分布。结果表明,相比于轧制前的再结晶状态,轧制变形后的高低温退火处理都在一定程度上提高了合金中低Σ重位点阵(Coincidence site lattice,ΣCSL)晶界的比例,增幅均达20%以上;但在其晶界特征分布(grain boundary character distribution,GBCD)中,互成Σ3n取向关系的晶粒团簇(Cluster of grains with Σ3n relationship,Σ3n CG)大小和其外围一般大角度晶界(random high angle grain boundary,HAB)网络的连接特性却存在明显差异。低温退火样品中Σ3n CG尺寸比高温样品大得多,且其HAB网络连通性被低ΣCSL晶界阻断的效果也明显优于高温退火样品。进一步对两个样品的织构和残余亚结构进行对比分析后认为,形变诱发晶界的优先迁移是低温退火样品中获得较大尺寸Σ3n CG和HAB网络连通性被低ΣCSL晶界有效阻断的重要原因。
Electron-back scatter diffraction (EBSD) technique was used to study the grain boundary characteristic distribution of 304 stainless steel after low temperature annealing and high temperature annealing in small deformation cold rolling (thickness reduction of 6%). The results show that, compared with the recrystallization state before rolling, the high and low temperature annealing after rolling deformation all improve the proportion of the grain boundary of the low ΣΣSL (ΣCSL) in the alloy to a certain extent, But their amplitudes are all above 20%. However, in the grain boundary character distribution (GBCD), the size of cluster of grains with Σ3n relationship (Σ3n CG) There are obvious differences in the connection characteristics of HAB network. The Σ3n CG size in the samples annealed at higher temperature is much larger than that in the samples at high temperature, and the interception of HAB network by the low ΣCSL grain boundaries is also better than that of the samples annealed at high temperature. Further comparative analysis of texture and residual substructure of the two samples suggests that the preferential migration of deformation-induced grain boundaries is the result of the larger size of Σ3n obtained in low-temperature annealed samples. The connectivity of CG and HAB network is effectively blocked by low ΣCSL grain boundaries important reason.