Tungsten–chromium–yttrium alloys as first wall armor material: Yttrium concentration, oxygen content and transmutation elements

•Y content of 0.6 wt% Y optimum for oxidation resistance of bulk smart alloy.•Degradation of oxidation resistance due to oxygen impurities in the alloy shown.•Re introduced in the alloy to investigate the effect caused by neutron irradiation.•Spatially heterogeneous simulation of the exposure to 14 MeV neutrons.•Depth resolved simulation of Re, V, H, and He production due to neutron irradiation.