Research area: Nanomaterials, biomaterials
Supervisors: Prof Namita Roy Choudhury and Prof Naba Dutta
Description: Thin film coatings are used for a wide variety of purposes, including protection from environmental attack, abrasive wear, erosion, impact and overheating. It is common for metallic components to be protected by ceramic coatings; several other types of substrate/coating combinations are also routinely employed.
Various coating deposition processes have been developed, including thermal spraying, electrostatic spraying, physical vapour deposition, chemical vapour deposition, surface oxidation, painting and plasma polymerisation. Organic coatings that have been applied with varying degrees of success include polyimides, polyurethanes, polyesters, polyacrylates and polystyrenes. These coatings have performed well in corrosion tests, and combinations of different polymer species allow the tailoring of properties such as thermal stability and electrical impedance. However, there are shortcomings in using some organic polymers because they can display the following undesirable features: a) they have hydrophilic characteristics, b) micro-organisms readily settle and grow on them; leading to degradation, c) they display poor wetting and adhesion to metals, and d) they usually form mechanically weak films.
One of the most interesting methods is to use hybrid coating based on fluoropolymer, phosphate and other nanostructured inorganics. The process enables to deposit corrosion resistant layers on a variety of substrates with reasonably high rate. Such polymer thin films should remain stable with good adhesion properties. Therefore, in this work we plan to deposit hybrid polymeric thin film on metallic substrates .
The process must lead to a high polymer density on the metal surface to prevent any adsorption of moisture and oxygen. Also, the resultant materials will be investigated by various gravimetric, spectroscopic, microscopic and electrochemical methods.