Semi-finished products of ferritic steel and catalytic substrate containing same

摘要

A ferritic, heat-resistant steel whose behavior at high application temperatures is improved by the combined addition of oxygen affinitive elements. Apart from stabilizing the electric resistance of heating elements by addition of zirconium, titanium and rare earth metal, also the creep elongation of the steel is considerably reduced under load at temperatures above 900 DEG C., the thermal stress capacity thus being increased. The resulting complex oxide coating increases the protective function with regard to preserving the metallic cross-section in continuous and/or cyclic heat treatments. The steel is composed of: up to 0.10 % C up to 0.80 % Si 0.10 to 0.50 % Mn up to 0.035 % P up to 0.020 % S 12 to 30 % Cr 0.10 to 1.0 % Mo up to 1 % Ni 3.5 to 8 % Al 0.01 to 1 % Zr 0.003 to 0.8 % rare earth metals 0.003 to 0.30 % Ti 0.003 to 0.050 % N remainder Fe and incidental impurities.