Adhesion at Metal-Ceramic Interfaces

Adhesion at Metal/Ceramic Interfaces

Goals | Introduction | Participants | Methods | Results | Acknowledgements

Goals:

The goal of this work is to use Density Functional methods to determine the structure, energetics, and bonding at heterophase interfaces between Aluminum alloys and technologically relevant ceramic substrates.

Introduction:

Interfaces between metal and ceramic play a vitally important role in many modern materials applications, including:

Heterogeneous Catalysis

Al processing

Semiconductor devices and Thin Film Growth

Metal-Matrix composites

Medical Implants

Thermal Barriers

Unfortunately, relatively little is known about the mechanisms which control fundamental properties such as adhesion at these interfaces. By way of first principles simulations based on Density Functional Theory, it is now possible to examine the electronic structure and thereby determine the critical factors which control the strength of the interfacial bonding, including the effects of the most common alloying elements.

Our work is a collaboration with scientists at ALCOA (formerly the Aluminum Company of America), who, along with assisting in the calculations, will utilize our results to aid in the selection of tool coating materials to help reduce adhesion in the Al manufacturing process. Our study will yield the first reliable database of metal-ceramic adhesion energies, and will serve as valuable tool in understanding the fundamental physics and chemistry of these systems.

Participants:

	Louis Hector, Jr. - Materials and Process Lab, General Motors
	Newton Ooi - Arizona State University
	Robab Shakiba - Arizona State University
	Jun Zhong - Arizona State University
	Jim Adams - Arizona State University

Methods:

First-principles based electronic structure calculations using the Vienna ab initio Simulation Package, VASP. Some features of VASP include:

Local and Gradient Corrected approximations for exchange and correlation

Plane wave basis set

Vanderbilt "Ultrasoft" pseudopotentials

Distributed memory parallelism

Efficient charge density mixing

Results, Publications and Presentations:

	Don's Ph.D. thesis
	Summary of results as of Aug 14, 2001 (Don's thesis defense presentation.)
	A preprint of our Al/WC paper is here.
	A preprint of our Al/VC vs Al/VN paper is here.
	A preprint of our Spring 2001 MRS proceeding paper is here.
	A picture of the Electron Localization Function for Al-terminated Al/Al₂O₃
	A reprint of our Fall 2000 MRS proceedings paper is here.
	A preprint of our Al(111)/Al₂O₃(0001) Interface Paper is here.
	A preprint of our mini-review article solicited by Surface and Interface Analysis is here.
	A preprint of our VPA on alumina paper is here (figures) and here (text).
	Various MRS and APS 2000 presentation viewgraphs are here.

Acknowledgements (funding and computational resources):

	National Science Foundation (GOALI Grant DMR-9619353)
	National Center for Supercomputer Applications
	General Motors
	ALCOA