Duration: 1995-1998

The DTI-Link Surface Engineering project 'Multicoat' was initiated in June 1995 to research and develop industrial scale TiAlN based superlattice and pseudo-multilayer structured PVD hard coatings for the cutting tool, glass mould and chemical engineering valve industries. The companies involved were as follows

• Hydra Tools International Ltd
• Dormer Tools (UK) Ltd
• British Glass Research Association
• The Casting Development Centre
• Taylor Valves

One of the main aims of the programme was the investigation and exploitation of pilot and full scale production advanced PVD coatings which possess enhanced high temperature oxidation and wear resistance ie for dry high speed milling, drilling operations, hot forming operations and Si based glass manufacture. 

Investigations have shown that the period of the superlattice layering could be reduced to a minimum of 19Å, the oxidation resistance could be maintained up to 950 degrees celsius and hardness could be varied from 2500-4500Hk. A selection of the new coating systems examined are shown below and have been independently performance bench-marked against a range of commercially available arc evaporation and electron beam TiN and TiAlN films.

TiAlN TiAlCrYN TiAlN-CrN + a range of CN stoichiometries and MoS2 top coats. TiAlN-VN TiAlN-ZrN Nb

Project staff: Professor P Eh Hovsepian