Abstract: The present invention relates to a product of ferritic stainless steel manufactured according to the process of this invention, which product has increased resistance to cyclic and continuous thermal load and oxidation at elevated temperatures and which has improved mechanical properties at said temperatures as well as use thereof in the form of wire, strip, foil and/or tube in high-temperature applications such as in catalytic converter applications, in heating and furnace applications and which has the following composition (in % by weight): less than 1% of Ni, 15-25% of Cr, 4.5-12% of Al, 0.5-4% of Mo, 0.01-1.2% of Nb, 0-0.5% of Ti, 0-0.5% of Y, Sc, Zr and/or Hf, 0-0.2% of one or more rare earth metals (REM) such as, for instance, Ce or La, 0-0.2% of C, 0-0.2% of N, with the balance iron and normally occurring impurities.

Abstract: The present invention relates to a method to produce an austenitic alloy by an austenitic stainless substrate alloy of low Al content being coated with an alloy of higher Al content at a temperature between 100° C. and 600° C., so that the resulting product has an Al content of 4.5-12% by weight.

Abstract: Ferritic steel alloyed with a balanced quantity of chromium, aluminium and reactive elements and that has the following composition (in % by weight): Ni up to 1 Cr 15-25 Al 0.75-3.7 Si max 0.6 Mo and/or W 0-3 Ti and/or Nb 0-1 Cup to 0.2 N up to 0.2 one or more of the reactive elements Zr, Hf and REM>0 balance iron and normally occurring impurities, wherein the equation Cr+3AI?26 is satisfied. The ferritic stainless steel is suitable for use as substrate material in catalytic converters for diesel engines in heavy vehicles at temperatures in the interval of 600-900° C. and a specific relation between the content of chromium and aluminium being satisfied.