Summary: | The conventional ion plating technique is described and the physical mechanism and energies involved in the technique reviewed. The triode (assisted discharge) ion plating is studied and it is shown to increase the ionization several times. Ion plating with a hollow cathode discharge is studied. The characteristics of the deposited film under these conditions are presented including thickness, adhesion and structure, and a comparison is made with ion plating in abnormal glow discharge. Carbon films have been deposited by both chemical vapour deposition and ion plating using methane cracking and arc and electron beam gun evaporation sources. Triode ion plating has also been used. It is found that the best way for depositing thick carbon films is the electron beam gun method. The optimum plating conditions are determined. The characteristics of the ion plated carbon films are studied. Diffraction studies indicate that the deposited carbon films are graphitic. Full structural details including graphiticity index, lattice parameters, grain size measurements are presented. Triode ion plating produces a more dense structure for carbon films. A pin-on-disc friction and wear rig has been designed and constructed. The friction and wear characteristics of ion plated carbon films have been studied in normal atmosphere and at higher temperature. It is concluded that the friction of ion plated carbon films is slightly higher than that reported for graphites, however, the film exhibits good-wear resistance. A numerical investigation of the relationship between surface topography and friction of ion plated carbon films is presented.
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