An activating flux for welding stainless steel includes: from 25 to 40 weight percent of titanium dioxide (TiO2); from 25 to 30 weight percent of chromium oxide (Cr2O3); from 10 to 30 weight percent of silicon dioxide (SiO2); from 10 to 15 weight percent of molybdenum disulphide (MoS2); and from 5 to 15 weight percent of molybdenum trioxide (MoO3), which are active additive materials. A welding rod or wire includes a welding material and an activating flux. The activating flux layer is provided on or in the welding rod or wire and is formed as an outer layer or a core portion of the welding rod or wire.