Observation of cold-rolling texture and partially recrystallized texture in polycrystalline 3 pct Si-Fe by high-resoluti
- PDF / 4,492,303 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 88 Downloads / 187 Views
SM of the development of recrystallized texture has been discussed for several decades in metallurgical science (e.g., References 1 through 8). The oriented nucleation theory and the oriented growth theory are still controversial. The oriented nucleation theory claims that the recrystallized texture is formed because of the preferred nucleation with a particular orientation. Burgers and Louwerse proposed this theory using a single crystal of aluminum.[1] The formation mechanism of recrystallization nuclei having Goss orientation was explained by Dunn et al. from the experiment using 3 pct Si-Fe single crystals.[2,3] The oriented growth theory asserts that the recrystallized texture is formed because of the difference in growth potential for each grain orientation. Barrett found from the study using Al or Cu single crystal that the recrystallized grains were related to the deformed matrix by a 45 deg 具111典 rotation.[4] Most studies of these kinds used single crystal because of the easiness of the orientation measurement. From a practical viewpoint, metals in use are mostly polycrystalline materials. In the single-crystal experiment, consideration on an influence of adjacent grains or that of grain boundaries is not necessary. Quite often, the behavior of recrystallization of polycrystalline material is different from that of a single crystal. Texture analysis should be done in polycrystalline materials. However, few works precisely treated the local orientation relationship between recrystallized and deformed grains in polycrystalline materials. This comes from the poor spatial resolution of the local orientation analysis of the deformed grain. Dense dislocation density induced by heavy deformation prevent the precise orientation measurement using conventional techniques. However, recent technical innovations of the electron backscattered diffraction T. IMAMURA, Researcher, Y. HAYAKAWA, Senior Researcher, and M. KUROSAWA, Senior Researcher, are with the Technical Research Laboratories, Kawasaki Steel Corporation, Kurashiki, 712-8511, Japan. Contact e-mail: [email protected] Manuscript submitted March 25, 2002. METALLURGICAL AND MATERIALS TRANSACTIONS A
(EBSD) method allow much more precise analyses than before.[9–13] The information on the orientations of deformed grains and their spatial arrangement can be obtained quantitatively. Some advanced attempts to investigate the origin of recrystallized texture using EBSD have been reported recently in steel research. Barnett et al.[14,15] confirmed using interstitial free steel that recrystallized grains belonging to ␥ -fiber (具111典// ND: normal direction) texture nucleated inside a deformed grain rather than at the grain boundary, which was conventionally considered as a preferable nucleation site.[16] In this experiment, ␥ -fiber recrystallized grain was generated from ␥ -fiber deformed grain. However, the studies of these kinds[14–18] are in most cases on the formation of ␥ -fiber recrystallized grains, which are desirable for obtaining deep drawability. O
Data Loading...
