Patent ID: 8349395

Claim:
A process for manufacturing a steel/ceramic composite suitable to form a connection between an interconnector and a cathode of a high temperature fuel cell and comprising an interconnector made of steel and an electrically conductive ceramic connection layer arranged on it, comprising following steps: a) providing an interconnector made of a ferritic steel comprising 18-24 weight % Cr; b) applying, between the interconnector and the cathode, a suspension or paste formed from a powder subjected to a heat treatment at a temperature between 500-700° C., the suspension or paste comprising a perovskite with the composition Ln 1-x Sr x Mn 1-y Co y O 3-δ or Ln 1-x Sr x Fe 1-y Co y O 3-δ ; where 0.1≦x≦0.4, 0.1≦y≦0.6, 0≦δ≦x/2, and Ln=La−Lu; c) heating together the interconnector, and the applied suspension or paste, and the cathode to a joining temperature between 800-900° C. to form the electrically conductive ceramic connection layer from the suspension or the paste; and (d) obtaining an initial contact resistance of less than R=0.01 Ωcm 2 at an interface of the interconnector and the electrically conductive ceramic connection layer.