Abstract: A lubricant film which prevents galling or sliding metal surfaces comprising: a solid lubricant comprising 60-80% wt % of MoS.sub.2 or MoS.sub.2 +graphite; a lubricant additive comprising at least one component which comprises 10-30% wt % of Sb.sub.2 O.sub.3, Fe powder Zn powder or Ag powder; and an organic binder comprising 3-15% by weight of at least one component selected from the group consisting of epoxy ester resin, acrylic resin and urea resin.

Abstract: An efficient method of descaling metal sheets, such as titanium and stainless steel sheets, which includes carrying out anodic electrolysis using a metal sheet as the anode while sliding an abrasive member relatively to and on the surface of the metal sheet, is disclosed. The abrasive member essentially constitutes a fabric-like material made of synthetic resin.

Abstract: A thin corrosion protective film of an iron oxide can be formed on the inner surface of a condenser tube made of a copper alloy by first applying on the inner surface a thin layer of an acidic suspension containing iron powder and then exposing the thus-coated inner surface to an atmosphere of an oxidizing gas. The above method can be carried out in a relatively short period of time and also in a relatively simple fashion. The resultant protective film is uniform and hardly reduces the thermal conductivity of the condenser tube, thus ideal as a protective film for condenser tubes of a heat exchanger.