The future objective is to demonstrate the feasibility of producing super adherent protective coatings at low processing
temperatures using energetic ion beams in conjunction with conventional
deposition techniques. There is an acute need for development of high quality, low temperature thin film deposition techniques that can achieve thin film qualities found in high temperature processes. Ion Beam Enhanced Deposition (IBED) promises a new generation of exotic coatings with superior adhesion, near theoretical densities, very high hardness, and, at the same time, capable of being deposited at low temperature. The effect of the ion beam is to initially intermix the deposited atoms with the substrate for superior adhesion as well as to provide energy to the grown layer for effectively high temperature processing at low substrate temperatures. Range of protective coatings such as TiN, HfN, ZrN, Al2O3 can be deposited by IBED. These films require characterization for their mechanical and chemical properties as well as microstructural analyses. Evaluation of mechanical properties include adhesion tests and wear tests. Microstructural analyses deemed necessary include - sputter Auger electron spectroscopy for compositional analysis, sputter ESCA for composition and chemical bonding information, glancing x-ray analysis for lattice structure, ion backscattering for nondestructive composition vs. depth information, and Scanning Electron Microscopy and Transimission Electron Microscopy for grain structure and lattice microstructure information. Ion beam assisted deposition processes improve the tribological and corrosion behaviour of parts without significantly altering the dimensions of the part, thereby eliminating the need for further machining operations and reducing overall production costs. The ion beam processes are maturing and can be scaled up. Ion beam assisted chromium and CrN coatings are finding applications in bearing assemblies, hydraulics and engine
components. Hard, extremely adherent hard coatings synthesized by the ion beam enhanced deposition technique are of interest to precision aerospace bearings and precision micropositioning platforms where a very thin 0.1-0.5 micrometer antifriction antiwear coating could be used without remachining or respecifying dimensions of critical components. Ever-increasing demand in various tribological situations (mainly friction and wear) have stimulated the development of a variety of innovative coatings, including single, duplex and multilayer systems. Multilayer coating systems have been intensively studied in recent years in order to enhance their tribological performance. Materials to be studied in the future programmes will include Ti compounds (e.g. CN/TiN, TiCN/TiN, TiC/TiN, TiN/Ti), or other refractory metal multilayer compounds for exotic properties. Furthermore, multilayer coatings can exhibit extremely high hardness, making them useful as abrasion-resistant surfaces. Hardness enhancement could be achieved by combining layers with different mechanical properties (TiN/VN, TiN/NbN, TiN/W2N) or compositionally modulated structures, where the thickness of the alternating films are appropriately controlled to achieve specific properties. Furthermore, superlattice structures can be formed, most often giving rise to a drastic increase in the overall hardness of the multilayer coating system. Hard chrome is used to coat high wear surfaces such as bearings shafts and hydraulic components and rebuild and remanufacture worn shaft and corroded hydraulic components. Cadmium electroplating is also used to impart corrosion resistance and lubricity to a vide variety of parts. Cd is a toxic metal and chrome operations use hexavalent Cr, a class one carcinogen. Metal or ceramic coatings deposited by PVD and or ion beam modified surfaces having superior properties form the next stage of development for various applications as cost effective and environmentally acceptable alternatives to electroplated chromium and cadmium applications. various alternatives are being supplememted for replacement of hard chrome coatings. Ion beam assisted deposition of coatings offer suitable alternative for the hard chrome coating thus paying the way for future development of hard, adherent coatings.