Formation of Deformation Band and Static Recrystallization Behavior of Hot Rolled Fe-19%Cr Ferritic Alloy

Abstract

The effects of initial grain size (1 000μm and 430μm), rolling temperature and reduction on the deformation structure and recrystallization behavior of a hot rolled Fe-19%Cr ferritic alloy were investigated. The characteristics of the deformation band formed by hot rolling and its effect on recrystallization were crystallographically studied. The main results are as follows.
(1) Above 1 000°C well defined subgrain substructures are observed. With increasing temperature, the subgrain size increases. In specimens hot rolled below 1 100°C, deformation bands are observed preferentially near grain boundary.
(2) The number of deformation bands increases with increasing rolling reduction or decreasing grain size. The deformation band and the matrix are correlated with a rotation in the range of 35°-55° around a <110> common axis. The orientations of deformation band and matrix are nearly <100>//N.D and <211>//N.D, or <211>//N.D and <100>//N.D The subgrain size of <100>//N.D orientation is coarse, compared with those of other orientations.
(3) The recrystallization occurs preferentially in the boundary area containing deformation bands. Recrystallized grains have almost the same orientation as the matrix or the deformation band. Decreasing the rolling reduction retards recrystallization, especially in coarse grained specimens. The retardation is attributed to the decrease of deformation bands.