While the problem of the identification of mechanisms of hydrogen‐assisted damage has and is being thoroughly studied, the quantitative analysis of such damage still lacks suitable tools. In fact, while, for instance, electron microscopy yields excellent characterization, the quantitative analysis of damage requires at the same time large field‐of‐views and high spatial resolution. Synchrotron X‐ray refraction techniques do possess both features. Herein, it is shown how synchrotron X‐ray refraction computed tomography (SXRCT) can quantify damage induced by hydrogen embrittlement in a lean duplex steel, yielding results that overperform even those achievable by synchrotron X‐ray absorption computed tomography. As already reported in the literature, but this time using a nondestructive technique, it is shown that the hydrogen charge does not penetrate to the center of tensile specimens. By the comparison between virgin and hydrogen‐charged specimens, it is deduced that cracks in the specimen bulk are due to the rolling process rather than hydrogen‐assisted. It is shown that (micro)cracks propagate from the surface of tensile specimens to the interior with increasing applied strain, and it is deduced that a significant crack propagation can only be observed short before rupture.

In-situ analysis of the strain evolution during welding using low transformation temperature filler materials Short Title: In-situ analysis of the strain evolution during welding using low transformation temperature filler materials Article Type: Research Article

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Hydrogen-charged supermartensitic steel samples were used to systematically investigate imaging artifacts in neutron radiography. Cadmium stencils were placed around the samples to shield the scintillator from excessive neutron radiation and to investigate the influence of the backlight effect. The contribution of scattered neutrons to the total detected intensity was investigated by additionally varying the sample-detector distance and applying a functional correlation between distance and intensity. Furthermore, the influence of the surface roughness on the edge effect due to refraction was investigated.

Residual stresses are crucial when assessing the performance of welded components. The present work deals with the possibilities of transferring the real-life boundary conditions of welding, which influence the residual stress, into the laboratory. The possibilities of a test system specifically developed for this purpose, with a maximum capacity of 2 MN, are shown, because the structural design, global process, geometry, and material-dependent stresses are induced, which can be simulated and quantified within the system. Additionally, X-ray diffraction can be applied to determine the resulting local stress distribution precisely with high spatial resolution. Two examples are presented to show how the conditions to be found during production are simulated in the laboratory. It is shown how welding stresses in high-strength steels are affected by the heat control. It was possible to clarify why elevated working temperatures significantly increase the bending stresses in the welded joint and therefore the tensile stresses in the heat-affected zone. The effect of heat treatment applied under stresses resulting from welding is demonstrated by the example of a creep-resistant steel. Reheat cracking is significantly increased in this case, as compared to small-scale laboratory-based tests.