It is proposed to develop new high pressure nitriding process which, compared to other nitriding methods, has the following advantages: - The rapid depassivation of the surface causes a quicker build-up of a enclosed nitride layer and thus it shortens treating time. - High alloyed and titanium materials can also be easily nitrided. - The precleaning of the parts can be limited to a minimum. - The results are not geometry-related. - A specific layer structure is possible by optimising of the process. - High repeatability of results. The objectives of this project are: -To develop a new high pressure nitriding process to increase lifetime and reliability of steels parts (forming and cutting tools, injection moulds and mechanical elements), usually nitrided by conventional techniques, increasing lifetime a 30% at least and reducing process time by a quarter against the conventional atmospheric gas nitriding. - To carry out a correct nitriding of parts and materials which cannot be nitrided by conventional techniques. namely injection nozzles and parts made of titanium alloys ( medical implants, aeronautic and bicycle parts) - To verify the technical feasibility of this new technology and to develop a new surface treatment process able to be exploited industrially. - To understand, in a general sense. the correlationship betveen the parameters of the process (gases, pressure, temperature, time) and the metallurgical, mechanical and tribological characteristics of the treated substrate.