PROBLEM TO BE SOLVED: To improve the oxidation resistance in a high-temperature and low- oxygen potential atmosphere by making a platinum group element present in a heat resistant metallic material and forming an oxide film having protectiveness on the surface of the metallic material.
SOLUTION: The platinum group element may be made to exist in the heat resistant metallic material by adding the element to the same. At this time, the platinum group element is preferably so added to the metallic material as to exist therein at a ratio of 0.01 to 30% by atomic % as the total amount of the platinum group element. The platinum group element may otherwise be made to exist on the surface part of the heat resistant metallic material with coating or infiltrating by sputtering, ion plating, plating, ion implanting, etc. In such a case, a working effect may be sufficiently obtained even by the use of a slight amount of the platinum group element. As a result, the formation of the dense oxide film consisting essentially of Cr and having protectiveness is accelerated during the use of, for example, ferrite steel, by which the oxidation resistance of the steel is greatly improved and the compatibility thereof with high-temperature strength is made easy.