Inhomogeneous deformation and recrystallization behavior of through-thickness tantalum sheet under one-cycle clock-rolling

Publication date: Available online 27 August 2019Source: Progress in Natural Science: Materials InternationalAuthor(s): Jialin Zhu, Shifeng Liu, Yu Zhang, Yahui Liu, Nan Lin, Yulong Zhu, Chao DengAbstractEffects of low clock rolling passes on through-thickness deformation and recrystallization behavior of the Ta sheet have been investigated. The clock-rolled samples with one cycle (8 passes) were systematically examined under different thickness layers. X-ray diffraction (XRD) and X-ray diffraction line profile analysis (XLPA) showed that the extremely inhomogeneous texture evolution generated and the bulk stored energy existed in the through-thickness clock-rolled Ta sheet after 8 passes. The electron backscatter diffraction (EBSD) results revealed the misorientation of the grains in the deformed samples, indicating that grain subdivision in the surface and center layer was more serious than that in the quarter layer. High intensities misorientation indicates the presence of microshear bands in the surface and center layer. During annealing, the difference of the stored energy and the fragmentation of deformation microstructure along the thickness led to a heterogeneous driving force for the nucleation of the grains, resulting in subsequent different recrystallization rate in the different regions of the sample.Graphical abstract
Source: Progress in Natural Science: Materials International - Category: Materials Science Source Type: research