Cr-Ni alloys that contain less than 50% steel and feature even better properties with regard to corrosion and heat resistance are no longer considered steels. These special alloys belong to the group of highly heat-resistant alloys, and are based on the NiCr8020 alloy type which was first described around 1906. The addition of aluminium and titanium gives them thermosetting properties and significantly increases stability at high temperatures. Modern trade names include Inconel, Incoloy, Hastelloy, Cronifer, Nicrofer. The latter is a highly corrosion-resistant nickel-chrome-molybdenum alloy, which is again subdivided into various alloys; they are used, among others, in turbo jet engines, power plants (gas turbines), the oils and gas industry, environmental technology (REA) as well as chemical process technology, hence any situation in which high stability must be continuously warranted at very high temperatures or under highly corrosive conditions.