In Memoriam: Charles J. McMahon (1933-2022)

Charles J. McMahon, Professor Emeritus in the Department of Materials Science and Engineering, passed away on December 10, 2022, at the age of 89.

Dr. McMahon grew up in the Germantown and East Mt. Airy neighborhoods of Philadelphia and attended the University of Pennsylvania on an NROTC scholarship, where he earned a bachelor’s degree in Metallurgical Engineering in 1955, becoming his family’s first college graduate.

After graduating from Penn, Dr. McMahon served aboard the battleship USS New Jersey and later as a communications officer and cryptographer on the minesweeper USS Thuban. Following three years of active duty, he enrolled in the Massachusetts Institute of Technology where he earned an Sc.D. in Physical Metallurgy in 1963.

Dr. McMahon then returned to Philadelphia to complete a postdoctoral fellowship in the newly formed Department of Metallurgy and Materials Science (now the Department of Materials Science and Engineering) in Penn Engineering. A year later, he joined the faculty of that department, where he remained throughout his career, serving as Chair from 1987 until 1992.

Dr. McMahon was one of the world’s leading authorities on steel fracture. His doctoral dissertation research led to a new understanding of the hydrogen-induced embrittlement in steel and paved the way for widespread use of new alloys in civil and industrial applications. His work contributed directly to saving lives on bridges and in buildings, as well as on ships. Dr. McMahon was elected to the National Academy of Engineering (NAE) in 1980.

At Penn, he trained two generations of graduate students and postdoctoral fellows in materials science who went on to become leaders in industry and academic engineering departments throughout the United States, Europe and Asia. In addition to his academic career at Penn, he spent sabbatical years at General Electric Research Labs in New York (1969), Cambridge University in England (1973), and University of Göttingen in Germany (1984).

Dr. McMahon was a pioneering educator who authored two textbooks aimed at introducing principles of materials science to undergraduates by examining the properties of familiar technology, mainly the structural components of the bicycle. He was an early adopter of interactive digital media and produced a series of video lectures and animated tutorials. His work as an educator was recognized by Penn Engineering’s S. Reid Warren, Jr. Award in 1992 and the University’s Lindback Award for Distinguished Teaching in 2001.

Dr. McMahon is survived by his wife Helen; children Charles (III), Elise, Robert and David; two grandchildren, four siblings and many nieces and nephews. He was preceded in death by his daughter Christine.

Dr. McMahon’s obituary was also published in the Philadelphia Inquirer on January 19, 2023.