2011 Kyoto Prize Laureates

Advanced Technology

Materials Science and Engineering

John Werner Cahn

/  Materials Scientist

1928 - 2016

Emeritus Senior NIST Fellow, National Institute of Standards and Technology/Affiliate Professor, University of Washington

Commemorative Lectures

Science during Paradigm Creation


11 /11 Fri

Place:Kyoto International Conference Center


“Materials Science and Engineering of Multi-component Systems and the Future Prospects”


11 /12 Sat

13:00 - 17:30

Place:Kyoto International Conference Center

Achievement Digest

Outstanding Contribution to Alloy Materials Engineering by the Establishment of Spinodal Decomposition Theory

Dr. John W. Cahn developed the theory of spinodal decomposition in alloy materials by incorporating the strain energy term into the free energy of the alloy system. It has made it possible to predict the optimal microstructures of alloy materials and to maximize their functions. The theory has led to the establishment of a design guideline for the development of alloy materials and contributed to the progress of both materials science and materials industry.


Among the structural and functional materials in common use today, only a few consist of a single component, while the large majority are alloy materials of two or more elements. To create alloy materials with ideal characteristics and functions, it is essential to control their composition and microstructure. Until the 1950s, researchers attempting to maximize the potential of alloy materials were forced to take a trial-and-error approach toward constituent selection and structural control, and design guides for optimizing the characteristics of alloy materials for specialized functions were eagerly sought.

The structure of an alloy material is determined by the requirement that its free energy of the alloy material must be a minimum. However, the techniques available to thermodynamics in the 1950s could deal mainly with homogeneous alloys. It was impossible to rigorously apply the free energy concept to controlling of the microstructure of heterogeneous alloys with microstructures formed by composition fluctuations.

Dr. John Werner Cahn established the theory of three-dimensional spinodal decomposition by extending the one-dimensional theory formulated by Dr. Mats Hillert and also by incorporating an elastic strain energy term into the free energy, leading to the intentional design of alloy materials with especially desirable characteristics. More specifically, Dr. Cahn became the first to demonstrate that the composition fluctuations needed to bring out the optimal properties of alloy materials may be determined by a materials structure formation theory based on the three dimensional spinodal decomposition, thereby proposing a technique to deal quantitatively with microstructures. This theory has since found application in the design and production of metals, glass, semiconductors, polymers, heat-resistant materials, and magnetic materials, which require a variety of properties and functions. Dr. Cahn’s research findings have also laid the foundations for the phase-field method, which is a structure formation simulation method, and also one of the hottest research topics of recent years.

As detailed above, Dr. Cahn made it possible to predict the optimal microstructures that would maximize the property and the functionality of alloy materials, by being the first to advocate that the formation and control of such materials’ microstructures resulting from spinodal decomposition may be determined by free energy in combination with elastic strain energy. Using this analysis and theory, materials scientists worldwide are now creating effective design guides for the development of new alloy materials. Consequently, Dr. Cahn’s work represents a significant contribution not only to the progress of materials science, but to the development of materials for modern society as a whole.

For these reasons, the Inamori Foundation is pleased to present the 2011 Kyoto Prize in Advanced Technology to Dr. John Werner Cahn.


Born in Cologne, Germany
Ph.D. (Physical Chemistry), University of California, Berkeley
Instructor, Institute for the Study of Metals, University of Chicago
Research Associate, Metallurgy and Ceramics Department, Research Laboratory, General Electric Company
Professor, Department of Materials Science, Massachusetts Institute of Technology
Center Scientist, Center for Materials Science, National Bureau of Standards
Senior Fellow, Materials Science and Engineering Laboratory, National Institute of Standards and Technology
Affiliate Professor, University of Washington
Emeritus Senior NIST Fellow, Materials Science and Engineering Laboratory, National Institute of Standards and Technology
Selected Awards and Honors
Acta Metallurgica Gold Medal
Von Hippel Award, Materials Research Society
Gold Medal, Japan Institute of Metals
National Medal of Science
Bower Award, The Franklin Institute
American Academy of Arts and Sciences, Japan Institute of Metals, National Academy of Engineering, National Academy of Sciences
Selected Publications
Spinodal Decomposition. The 1967 Institute of Metals Lecture, TMS AIME 242: 166-180, 1968
A Microscopic Theory for Antiphase Boundary Motion and Its Application to Antiphase Domain Coarsening (Allen, S. M. and Cahn, J. W.). Acta Metallurgica 27: 1085-1095, 1979
A Metallic Phase with Long-Ranged Orientational Order and No Translational Symmetry (Shechtman, D. S., Blech, I., Gratias, D. and Cahn, J. W.). Physical Review Letters 53: 1951-1953, 1984
The Interactions of Composition and Stress in Crystalline Solids (Larché, F. C. and Cahn, J. W.). Acta Metallurgica 33: 331-367, 1985
The Cahn-Hilliard Equation: Motion by the Laplacian of the Mean Curvature (Novick-Cohen, A., Cahn, J. W. and Elliott, C. M.). European Journal of Applied Mathematics 7: 287-301, 1996

Profile is at the time of the award.