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NIST Materials Science Pioneer John Cahn To Receive Bower Award from Franklin Institute

For Immediate Release: January 28, 2002


Contact: Mark Bello

The Department of Commerce's National Institute of Standards and Technology (NIST) announced today that materials scientist John Cahn will receive the 2002 Bower Award and Prize for Achievement in Science from the Franklin Institute. Cahn is considered to be among the most influential theorists in his field over the past half century.

A winner of the 1998 National Medal of Science, Cahn, who came to NIST in 1977, is being recognized for "his lifelong dedication to understanding materials, his influence and inspiration upon generations of scientists and engineers, and his seminal contributions to the understanding of the thermodynamics and kinetics of phase transformation."

Initially motivated by a desire to place the millenniums-old craft of metal-making on solid scientific footing, Cahn's theories have sprouted productive lines of research not only in metallurgy but also in physics, mathematics, chemistry, engineering, economics and demography.

Early in his career, Cahn was vexed by the failure of prevailing theory to account for the clumping and segregating of atoms during metals processing. With John Hilliard, a colleague at General Electric, he developed a "simple generic equation" to explain the phenomenon known as phase separation.

Since it was first published in 1961, the Cahn-Hilliard equation has become a pillar of materials science and engineering. It has been used to explain occurrences ranging from the simple (such as the curdling of cream in coffee and the formation of frost patterns on windshields) to the complex (such as the clumping of galaxies in the early universe and the evolution of settlement patterns in urban areas). The equation also underpins methods used to improve the sharpness of vague images.

"Being the father of an equation is like being the father of children," Cahn said recently. "They eventually take on a life of their own and develop in ways that could not be imagined when they were born."

Cahn also was a key member of the team contributing to the discovery of "quasicrystals" in 1984 by NIST guest researcher Dan Shechtman. The peculiar symmetrical arrangement, found in a rapidly cooled alloy, was not allowed by long-established laws of crystallography. Skeptics at the time argued that the observed "five-fold symmetry" of quasicrystals was not even allowed by nature.

The discovery launched several whole new fields of investigation. Practical payoffs to date include inexpensive non-scratch, non-stick coatings for cookware and hardening agents for medical instruments. Many other uses are expected.

Over his 50-year career, Cahn has made many significant contributions to the progress of materials and mathematics research. He has published about 250 scientific papers, delivered 400 invited lectures on his work and received numerous national and international honors and awards.

Born in Cologne, Germany, Cahn and his family immigrated to the United States in 1939, when he was 11, and settled in Brooklyn, N.Y. To escape Nazi pursuit, Cahn's father fled with his family from Germany in 1933 and lived for periods in Belgium, Holland and Italy. He became a U.S. citizen in 1945 and, a year later, began service in the U.S. Army.

Prior to coming to NIST, Cahn served as a research associate at General Electric and as a professor of materials science at the Massachusetts Institute of Technology. He earned his Ph.D. in physical chemistry in 1953 from the University of California at Berkeley.

Endowed by a Philadelphia chemical manufacturer, the first Bower Award and Prize for Achievement in Science was given in 1990. The award carries a cash prize of $250,000. Cahn and seven other leaders in science, engineering and business will be honored by the Franklin Institute during ceremonies to be held on Thursday, April 25, 2002, at the Benjamin Franklin National Memorial, Philadelphia.

As a non-regulatory agency of the U.S. Department of Commerce's Technology Administration, NIST develops and promotes measurements, standards, and technology to enhance productivity, facilitate trade, and improve the quality of life.