CAREER: A Faculty Early Career Program in Development of Superhard Coatings for Improved Performances

University Of South Florida, Tampa FL

Investigators

Abstract

Superhard coating systems for next generation materials applications must exhibit a combination of physical properties which include excellent thermal and chemical stability, wear resistance, high hardness, toughness, and good adhesion. The goal of this CAREER program is to develop a means by which application specific coatings can be efficiently designed, using an integrated approach tailored towards rapid scale-up and industrial production. The specific objective of this study is to understand structure-property relationships in advanced engineering superhard coating materials prepared by pulsed laser assisted physical vapor deposition (PVD) and by filament assisted chemical vapor deposition (CVD) techniques for multifunctional applications. The pulsed laser deposition (PLD) process promises a new generation of exotic coatings which have superior adhesion, near theoretical densities, and very high hardness, and which, at the same time can be deposited at low temperature. Superhard coatings of carbon nitride (CNx), cubic boron nitride (c-BN), diamond-like carbon (DLC) and microlaminate coatings of metal/ceramic materials will be fabricated by the PLD method. Very-high density CVD plasma will be explored for rapid growth of transparent diamond films at low substrate temperature with desirable microstructure that provides better mechanical properties for manufacturing applications. Evaluation of mechanical properties will include nanoindentation, adhesion and wear tests. Microstructural analyses will include X-ray diffraction analysis for lattice structure, and SEM, TEM and AFM for grain structure and lattice microstructural information. Efforts will be made to work with the industrial partners in developing potential commercial products. An important feature of the project is the training of graduate and undergraduate students in a fundamentally and technologically significant area of Materials Science research related to synthesis, structure, properties and performance. The education plan involves the development of a module on 'Thin Film Technology' that illustrates key aspects of materials processing with appropriate emphasis on synthesis, selection of materials for substrate and film, deposition processes, microstructural development, mechanical properties, kinetics and thermodynamics, and applications in industrial sectors, for instruction in cross-disciplinary fields. The module will include multimedia teaching resources and in-class demonstration. Special attempts will be made to attract students from under represented groups and to train them in multidisciplinary research.