Alumina coatings are to be deposited on to tool steel cutting and forming tools in an attempt to obtain improvements in performance which are substantially greater than those currently afforded by titanium nitride coatings. Deposition will be carried out at atmospheric pressure using aluminium chloride precursor obtained by the evaporation of powder rather than by reaction between hydrogen chloride and aluminium. The feasibility of this deposition route has already been established in the laboratory; as also has the necessity for a precoating on the tool steels. Following completion of this laboratory-scale research, a pilot-scale CVD reactor will be constructed, and the deposition conditions for the precoating and alumina coating established in the laboratory will be scaled-up and transferred to this reactor. A range of tool steel cutting and forming tools will then be selected and these tools coated with alumina in the pilot-scale reactor. Both conventionally produced and atmosphere-sintered tool steels are to be employed in an attempt to optimise coating/substrate combinations for different applications. Comparative testing of the alumina coated tools against titanium nitride coated tools will then be performed, both in the laboratory and also under industrial conditions.
Fields of science
- natural scienceschemical sciencesinorganic chemistrytransition metals
- natural scienceschemical sciencesinorganic chemistrypost-transition metals
- engineering and technologymaterials engineeringcoating and films
- natural sciencesearth and related environmental sciencesatmospheric sciencesmeteorologyatmospheric pressure