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In this paper, two identical American Iron and Steel Institute 1008 steels sheets were welded together in a butt joint configuration, with the welding line direction parallel to the rolling direction. The sheets were welded using the electron-beam welding technique. Stress distribution was monitored in the surface and the bulk of the welded samples using X-ray Bragg–Brentano and neutron diffraction methods, respectively. Accordingly, surface and bulk magnetic properties, namely magnetic Barkhausen noise and quasi-dc permeability, were monitored in the same area. Both surface and bulk magnetic measurements exhibit good agreement with the surface and bulk stress measurements obtained by the diffraction methods, after a proper calibration procedure. Complementary measurements with scanning electron microscopy and Vicker’s microhardness tester provide similar good agreement between the microstructural characterization and the residual stress distribution. [ABSTRACT FROM AUTHOR]

The paper investigated the residual strain and stress distribution, microstructure, and macro-texture along the transverse direction of commercially pure titanium grade 2 samples prepared by the CONFORM ECAP technique. This method belongs to the severe plastic deformation methods; hence, it could be assumed that residual stress fields would be present in the work-pieces. Residual stresses cannot be directly measured; thus, neutron diffraction measurements, Electron back-scatter diffraction (EBSD) investigations, and local X-ray macro-texture measurements were performed in different regions of the sample to determine the data for the residual stress calculation. The calculation was based on the modified Kröner model. Neutron diffraction strain scans and residual stress calculations revealed that symmetrical residual strain and stress gradients with compression character were present in the axial and hoop direction after one and two passes. Asymmetric distribution of the residual strains and stresses remained after the third pass of the CONFORM ECAP. EBSD investigations showed that after the first pass, significant grain refinement occurred; however, further passes did not cause any dramatic grain refinement. X-ray texture measurements revealed that local macro-texture was dependent on the number of passes of the CONFORM ECAP and on the investigated area in the samples. [ABSTRACT FROM AUTHOR]

Cold processing of tungsten heavy alloys is a challenge, however masterable owing to the continuing development in forming technologies. This study deals with a thorough investigation of a WNiCo alloy rotary swaged at room temperature. Due to the low processing temperature, special focus is on residual stress evaluation, which was performed by means of neutron diffraction and scanning electron microscopy and supplemented with numerically predicted stress distributions. (Sub)structure of the swaged-piece was analysed via scanning and transmission electron microscopy and the whole study was completed with tensile tests results. The results showed a substructure featuring dislocation cells and subgrains supporting the observed work hardening. For the swaged-piece, the ultimate tensile strength exceeded 1800 MPa. Analyses of grains misorientations indicated the presence of residual stresses especially on the swaged-piece periphery. This result was confirmed by the other performed analyses, all showing predominantly compression residual stresses within the swaged-piece, locally exceeding – 1500 MPa. [ABSTRACT FROM AUTHOR]