Recrystallization and Related Phenomena. Numerical Analysis on Earing Behavior in Drawn Cups of Steels Based on Finite Difference of Orientation Distribution Function.

Earing behavior in cylindric drawn cups of conventional single-reduced steel sheets and double-reduced steel sheets has been compared with the result predicted by the calculation from the orientation distribution function (ODF) data. Although the earing ratio of the cups of double-reduced steel sheets was larger than that of single-reduced steel sheets, the earing behavior of those steel sheets could be predicted by the same calculating model, in spite of the difference in type of cold-rolling process. This suggests that the second cold-rolling under 15% reduction little affected the manner in slip deformation during drawing. So it was concluded that the difference of earing behavior among the steel sheets was mainly caused by the difference of their textures. To discuss the effect of texture on the earing behavior, the finite difference of ODF (Δf(g)) was defined. A reliability of a result calculated from Δf(g) was confirmed by a comparison with a result directly calculated from ODF data. By using the positive and negative parts of the finite difference of the ODF, effects of increased and decreased components on the difference of the earing behavior were separated from each other. It was clarified that the influence of minor components (f(g)<1) on the earing behavior was not negligible in quantitative discussion of correlation between texture and earing behavior.