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4Voestalpine, Linz, Austria temperature tensile tests, and efforts are still needed to understand the crack formation mechanisms [4]. However, the internal stress situation which may lead to damage initiation and propagation during continuous casting is still unknown. The current work describes an experimental approach by non-destructive testing to determine the evolution of internal stresses under simulated production conditions. ExperimentalAngle dispersive neutron diffraction [5] was carried out for a 4.8 wt.% Ni containing low carbon steel alloy during cooling from casting. Samples of 2 × 5 x 15 cm 3 were cut from the surface of the slab representative for the cross section affected by heterogeneous cooling. An induction furnace was mounted on the sample table of the strain scanner to induce a thermal gradient (Fig. 1a). The coil was set on top of the sample and an actively cooled by a Cu heat sink from the bottom. After a stable mean thermal gradient of ~ 10 K/mm (Fig. 1b) was established, the induction coil was deactivated and the sample cooled from the bottom. Each scanned point was first heated to 1300 °C (100 % austenitic condition) and held for 15 min before establishing the thermal gradient. A monochromatic neutron beam was continuously diffracted (1 min/scan) in the center of the steel sample within a gauge volume of 5 × 5 x 5 mm³ penetrating 2 cm in the steel sample. The temperature dependent phase strain values in austenite (311) and ferrite (211) at several depth positions (4, 6 and 8 cm from the bottom) were determined relatively to a stress free reference sample (cylindrical, d ~ 3 mm, l ~ 10 mm) < gauge volume without dendritic morphology extracted from the surface of the slab. Abstract:In the steel industry, steel slabs are produced by continuous casting to allow fast processing. A complex stress state leads to crack formation in such steel slabs. The stress components relevant for failure were identified by neutron diffraction under simulated casting conditions. Eigenspannungen in StranggussbrammenZusammenfassung: Stahl wird industriell mittels eines kontinuierlichen Gussprozesses erzeugt, um rasche Produktion zu gewähren. In Stranggussbrammen führen Eigenspannungen zu Rissbildung, welche mittels Neutronenstreuung, zerstörungsfrei, unter simulierten Gussbedingungen identifiziert werden konnten.

New materials have to be developed for fusion reactor systems to withstand the high thermal load and heavy irradiation under service conditions. The divertor element collects the residuals of the nuclear reaction and withdraws heat from the reaction chamber into a heat sink. A thermal flux of ≈20 W mK−1 can be expected in such components. A plasma facing W plate is attached to a CuCrZr heat sink suffering CTE mismatch stresses at the interface due to pulsed operation required for the Tokamak reactor design. Fiber reinforced metal matrix composites are applied as an interlayer to reduce macroscopic interfacial stresses in these components. W‐wire reinforced copper is a promising material for this application due to a good fiber‐matrix bonding strength which is further increased by surface etching or graded interface designs. Thermal stresses in between the matrix and the wires are responsible for thermal fatigue damage within the constituents and at their interface. Neutron and synchrotron diffraction was performed in situ during thermal cycling to determine the micro stress amplitudes and their changes under simulated service conditions.