TEXTURE EVOLUTION BY GRAIN-GROWTH IN THE PRESENCE OF MNS AND ALN PRECIPITATES IN FE-3-PERCENT SI ALLOY

Texture evolution by grain growth in the presence of MnS and AIN precipitates in Fe-3% Si alloy was investigated by X-ray diffraction and electron channelling technique. Two texture groups A and B evolved from the primary texture (grain diameter of 6 μm) composed mainly of {111} 〈112〉 oriented grains. The group A (grain diameter of 2600 μm) were mainly composed of two subgroups, one with Goss oriented grains and another with Goss oriented grains rotated around ND axis by about 15 and 20°, while the group B (grain diameter of 700 μm) had an intensity level of about one seventh of that of the group A and had orientations centering around {112} 〈110〉. The ideal Goss or near Goss oriented grains of group A were infrequent in the primary recrystallized structure and made few Σ1 boundaries. They made large numbers of Σ9 boundaries though, or had a large value of the product (number of grains at orientation × number of σ9 boundaries made by them). The grains in orientations within the texture group B were fairly frequent in the primary structure and made large numbers of Σ1 boundaries. The value of the product (number of grains at orientation × number of Σ9 boundaries made by them) was large. The mechanism of the evolution of the A and B groups is considered to be due to (1), the higher mobility, in the presence of precipitate inhibitors, of adjacent grains in Σ9 coincidence or in coincidence orientations with a 〈110〉 rotation axis; (2), because Σ1 related grains are stable and less mobile under these conditions. © 1990.