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Abstract Microstructure and mechanical properties of the as-annealed Ti-stabilized Fe-17Cr ferritic stainless steel were investigated by scanning electron microscopy (SEM), electron backscatter diffraction (EBSD) and tensile tests. Experimental results show that the size of the ferrite grain in the Fe-17Cr stainless steel is about 40 µm after rolling and annealing. Orientation distribution function (ODF) by EBSD indicates that nearly homogeneous {111} annealing texture is produced in the annealed sheets. Pole figures (PF) by EBSD show that Kurdjumov–Sachs orientation relationship between the TiN particles and ferrite grains is established in the as-annealed microstructure. Tensile tests demonstrate that the yield strength (YS), ultimate tensile strength (UTS), and elongation (EL) of the as-annealed Ti-stabilized Fe-17Cr ferritic stainless steel are 319 MPa, 626 MPa, and 36.5%, respectively. In the SEM micrograph of the fracture, deep dimples can be observed and TiN particles can be found in the core of the dimples, which indicates that the samples undergo large deformation before fracture. [ABSTRACT FROM AUTHOR]

The resolution dependence of orientation gradients was studied in a well-annealed 99.9995% pure polycrystalline copper pulled to failure in tension. Owing to the well developed neck, different regions in the sample correspond to different tensile strains. Post-mortem characterization was performed using EBSD on cross-sections containing the tensile axis. Kernel average misorientation (KAM) was calculated as a metric to establish correlation between defect accumulation and microstructural features, with a threshold of 5° to focus on intra-granular gradients. The region with the lowest strain (2%) showed high KAM values adjacent to grain boundaries compared to the grain interior, regardless of the point spacing, i.e. the spatial resolution. However, in the region with the highest strain (13%) a strong dependence on resolution was found. For point spacings of 0.5 μm or smaller, the same correlation of high KAM with locations near boundaries was found. At coarse spacings i.e. low spatial resolution, by contrast, the reverse was found in that the highest KAM values appear in the grain interiors, as previously observed in X-ray microscopy on the same sample which had a similar coarse resolution. An analysis of orientation gradients parallel to, and perpendicular to boundaries suggested that the latter tend to be the larger of the two. This helps to explain why boundary-adjacent points have low KAM values. The conclusion is that measurement of local orientation gradient requires a resolution that is comparable to the dislocation substructure. [ABSTRACT FROM AUTHOR]