Different metals have been tested with respect to their thermal shock behavior simulating the slow energy deposition regime of NET. The metals evaluated for grain growth phenomena, melting, crack formation, recrystallization and partly their tensile properties after testing were W, W26Re, Mo, TZM, Nb, Ta, 1.4311 steel, Cu, and Ti6A14V. Thermal shock testing was performed using a 150 kV electron beam with a maximum input power density of 200 MW/m2 and a pulse length of 10 to 2000 ms.The tendency for crack formation is highest for W followed by TZM and W26Re. Mo samples formed only a few cracks during testing. No cracks could be observed on Cu, Ti, Nb, Ta, and steel samples. The tendency for crack formation for refractory metals is strongly dependent on grain orientation. The substrate temperature affects the tendency for crack formation too. Above a certain temperature, crack formation was not observed on W and Mo and their alloys. Thermal shock testing of tensile specimens, according to the slow energy deposition regime of NET, changes only to a small extent the UTS and strain. However, tensile strain is more affected than UTS by thermal shock testing above the melting threshold line.
Fracture behavior of tungsten-based composites exposed to steady-state/transient hydrogen plasma