Chemical-thermal treatment of parts

A method of chemical-thermal treatment comprises thermal treatment of the parts in a nitrogen-containing atmosphere at a temperature of no more than 680 DEG C thereby forming a carbonitride or oxynitride phase having a thickness of at least 5 mu m, forming on the parts a porous structure, exposing the parts to an oxidizing atmosphere at a temperature equal to that of thermal treatment, and subsequently filling the pores of the porous structure with oil containing 0.5-10 mass % of sulphur. The diffusion coating on parts made of aluminium-based alloys consists of crystalline structures of Al2O3 and of oxynitride phase of the (A1Me)2-3 (NO) type, where Me is metal. The diffusion coating on parts made of iron-based alloys consists of three structural components the first from the surface component has a fine-porous structure consisting, mainly, of Fe3O4 with pores filled with oil containing 0.5 - 10 mass % of sulphur, the second component has a nonporous structure of a carbonitride phase of the Fe2-3, (NC) type, and the third component has the bainite structure. An installation for realizing the method illustrated in the Fig. comprises the following units communicated with one another through a transport system:- a furnace 6 for thermal treatment of parts connected hermetically with a chamber 9 for isothermal holding of the parts which, in its turn, is connected hermetically with an oxidizing chamber 12 in the direction of moving the parts, a cooling chamber 15, and a chamber 21 for tempering the parts.