The manipulation of the rate of atomic transport along and across interfaces (most notably grain boundaries) remains a central theme in the control of the microstructure and properties of inorganic materials. This is described as the field of interfacial kinetic engineering of materials. In his opening Sosman Memorial lecture in 1973, David Kingery proposed a set of plausible concepts which he considered to be necessary and sufficient for the interpretation of ceramic grain-boundary phenomena, which provided an early foundation for conducting interfacial kinetic engineering. This 2008 Sosman Memorial lecture will attempt to provide both a retrospective assessment and a prospective viewpoint of this persistently challenging field of study.

A noteworthy new concept that has emerged is that of grain boundary complexions, which is considered to have important implications to the field of kinetic engineering in a wide variety of both ceramic and metal systems.

(Martin P. Harmer is the Alcoa Professor of materials science and
engineering and the director of the Center for Advanced Materials and
Nanotechnology at Lehigh University, Bethlehem, Pa. Harmer received a
B.S. (1976), Ph.D. (1980) and D.Sc. (1995) in ceramics from the
University of Leeds in England. His thesis advisor was professor Sir
Richard Brook. He spent a year (1978) at the University of
California-Berkeley learning electron microscopy under professor Gareth
Thomas. He joined the Lehigh faculty as an assistant professor (1980).
His research has focused on the control of interfacial transport
processes and microstructure in structural and electronic ceramics. He
has published approximately 250 technical papers, many of which have
appeared in the Journal of the American Ceramic Society.)