Parallel Atomistic Simulations of Nanophase Ceramics and Ceramic Composites

The aim of this research project is to gain deeper understanding for mechanical failure at interfaces and in nanophase materials by doing computer simulations on-very large systems (molecular-dynamics for millions of atoms). Thin-film coatings used to improve the wear, corrosion, and thermal resistance of metals often show interface failure problems. Most commonly this is delamination resulting from residual stress due to lattice mismatch or difference in the thermal expansion coefficients. Mechanical failure may occur either under operating conditions or during production. Extensive testing concerning the durability is of great importance. The present project will focus on two systems: Al/A12 O3 and Al/SiC. Of special interest are the structure, stress and strain distributions, and mechanical failure at the interface. Molecular-dynamics simulations on parallel computers will be` performed to investigate these properties. Ceramics have a great deal of potential for technological applications because of their high strength, low density, and corrosion and wear resistance. The disadvantage in this materials lies in their brittle`s. Recently it has become possible to synthesize less brittle ceramics by sintering nanometer size clusters. These special mechanical properties of such materials in their microstructure is objective of the multimillion particle simulations proposed for this project.