Abstract: The invention provides a method of producing an oxidation-resistant metallic part which exhibits sufficiently good oxidation resistance even in an oxidation atmosphere. The method includes the step of applying mechanical energy to a surface of a metallic part in the presence of particulates, and forming a protective coating in a surface of the metallic part. When the metallic part thus treated is exposed in a high temperature-oxidation atmosphere, the protective coating is oxidized to restrain the proceeding of the oxidation of the metallic part, that is the internally proceeding formation of TiO 2, thus serving a remarkable improvement of the oxidation resistance.

Abstract: Surface-treating metallic parts are produced by applying mechanical energy to the surface of a metallic part and to a substance on or near the surface of the metallic part. The substance is different from the metallic part in composition. The applying step forms a mechanically-alloyed layer from the metallic part and the substance in the surface of the metallic part. The surface-modified layer such as the mechanically-alloyed layer is a non-peeling alloyed layer having a composition or structure different from that of the metallic part. The method is effective in surface-treating light metal materials of which the surfaces are difficult to treat. For example, the method is applicable to soft Mg alloys and Al alloys to improve their surface hardness, and the thus-treated alloys are usable in slide parts which are required to have good wear resistance.

Abstract: A ferritic heat-resistant cast steel includes C in an amount of from 0.1 to 0.4% by weight, Si in an amount of from 0.5 to 2.0% by weight, Mn in an amount of 1.0% by weight or less, S in an amount of from 0.06 to 0.20% by weight, Ni in an amount of 1.0% by weight or less, Cr in an amount of from 13 to 20% by weight, V in an amount of from 0.2 to 1.0% by weight, at least one element selected from the group consisting of Nb in an amount of from 0.1 to 0.4% by weight, Mo in an amount of from 0.1 to 2.0% by weight, and W in an amount of from 0.2 to 4.0% by weight, and the balance of Fe and inevitable impurities, the S being dispersed as sulfides in the ferritic heat-resistant cast steel. It can further include at least one element selected from the group consisting of Te in an amount of from 0.01 to 0.1% by weight and Al in an amount of from 0.01 to 0.5% by weight. It can be produced by melting and casting the alloying elements and thereafter by annealing the resulting cast product at a temperature of from 750.

Abstract: A heat-resistant alloy having excellent properties at high temperatures and useful for producing exhaust valves, comprises, in weight %, not more than 0.10% C, not more than 2.0% Si, not more than 2.0% Mn, from 35 to 50% Ni, from 17 to 25% Cr, from 3.2 to 5% Mo, from 2.0 to 3.2% Ti, from 0.5 to 1.5% Al, with the balance consisting essentially of Fe, wherein the weight ratio of Ti/Al is not more than 5/1. The alloy may further comprise at least one of B, Ca, and Mg, and/or at least one of Nb and Ta.