Preface

The Twelfth Annual International Conference of the Los Alamos National Laboratory Center for Nonlinear Studies (CNLS), entitled "Nonlinearity in Materials Science", was held 18-22 May 1992 at the J. Robert Oppenheimer Study Center at the Los Alamo. National Laboratory. The conference focused on the role of nonlinear phenomena in materials sc~.,ce, particularly for those systems that involve mesoscopic length scales.

In many respects, materials science is a science of nonlinear phenomena. The basic nonlinear themes of coherent structures and order, chaos, and complex coiafigurations and pattern selection abound from the level of materials processing and synthesis to the most microscopic construction of material models. Often, the materials scientist might not view his problems along these thematic lines. Just as often, the nonlinear scientist might not look to material phenomena for examples of nonlinear phenomena. In the conference, we sought to present to the nonlinear scientist a sampling of the nonlinear phenomena and issues in the science of materials that might potentially define new areas of nonlinear research. We also sought to present to the material scientist developments in the science of nonlinear phenomena that might potentially impact materials research.

We constructed the agenda of the meeting to start with a overview of materials problems facing several major industries. These presentations were followed with presentations describing the state of the modeling of the important nonlinear materials problems of plastic flow and fracture. These talks led to discussions of modeling phenomena such as condensation and crystal growth whicb are central to materials synthesis and processing. The emerging role of computer simulations, new analytic and numerical techniques, and advance instrumentation in providing information and testing models in an unprecedented manner was also highlighted. In general, we sought to assess where the field of materials science stands in the context of nonlinear phenomena, where things needed to go, and what some of the tools might be to get there.

The articles in these proceedings are representative of the exciting scientific presentations that marked the conference. We hope the readers of these proceedings will be able to sense this excitement. We thank the speakers and the presentors of papers in the poster session for their efforts and cooperation in the preparation of their manuscripts.

We also thank the session chairpersons - Richard LeSar, Terry Lowe, Tony Rollet, Richard Silver, and Darryl Smith - for their encouraging discussion and scientific exchange, and give special thanks to Kay Adams for her banquet talk on joint Department of Energy and Los Alamos efforts at developing partnerships between industry and national laboratories. Additional thanks go to Jim Krumhansl, Richard LeSar, Terry Mitchell, Tony Rollet, and Darryl Smith for advice and assistance in selecting speakers for the conference.

We gratefully acknowledge the US Department of Energy, Office of Scientific Computing, for its essential support of the conference. As usual the CNLS administrative staff, and in particular Barbara Rhodes, provided excellent organizational and secretarial support. Finally, we are grateful to Los Alamos National Laboratory and its Director Sig Hecker for making available the Laboratory's excellent conference facilities and organizational staff.

Alan Bishop Robert Ecke James Gubernatis

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