In recognition of his outstanding achievements in the fields of hydrodynamic, elastohydrodynamic and mixed-film lubrication.
Born on 15 November 1929 in Shanghai, China, Herbert S Cheng came to the United States in 1950 to study at the University of Michigan. After obtain his BS in Mechanical Engineering, he served in industry as a design engineer, developing automatic transmissions and package machines. In 1957 he joined the University of Pennsylvania as an instructor, where he completed his graduate work. His research career began in 1962 at Mechanical Technical Inc. It was there that he initiated much of his early pioneering work in gas, elastohydrodynamic, seal and plastohydrodynamic lubrication. His contributions have provided an important impetus for the further development in these fields.
Returning to academic life in 1968 as an Associate Professor at the Northwestern University, he continued his pioneering research in tribology. In his studies on rolling and sliding cylinders, the effects of temperature on elastohydrodynamic lubrication were first analysed by Professor Cheng. Through his subsequent work on side leakage, pressure viscosity, inlet heating, and transient effects on EHL, he acquired an international reputation as an outstanding researcher in these fields.
During work on the development of a working seal concept for supersonic transport engines, the basic understanding of the behaviour of such seals was first evolved through Professor Cheng’s work. In his pioneering analytical work: “Plastohydrodynamic Lubrication” he revealed the effects of hydrodynamic lubrication on high speed cold rolling of metallic strip.
During the past 12 years, Professor Cheng has concentrated on the understanding of the mechanisms of lubrication breakdown, especially of the effects of surface roughness on hydrodynamic and elastohydrodynamic lubrication. He developed a new method, known as the Average Flow Model, to account for the effects of three dimensional surface roughness in the mixed-film lubrication regime, which is now used worldwide for the prediction of mixed-film lubrication performance.
Professor Cheng has also distinguished himself in the development of analytical methods for the prediction of contact failure and scuffing threshold, and developed an experimental validated analytical model for the prediction of scuffing loads or speeds, based on breakdown of micro EHL film and absorbed surface films.
Professor Cheng is also an effective team researcher. In 1984, he recognised the need for collaboration among researchers in mechanics, materials science, chemistry, and mechanical engineering, which led him to organise and establish the nation’s first Industry/University Co-operative Research Centre for Tribology, supported jointly by the National Science Foundation and a consortium of US Companies, to conduct basic and applied research for enhancing the reliability of tribological components in US industries. The Centre is continuing to serve the critical industrial needs in this area. He has, therefore, played an important role in building a firm bridge between university researchers and engineers in industry.
As an educator, Cheng has trained graduate engineers, PhD’s and Masters in tribology and mechanical design, many of whom are now serving in key positions either in universities or in the mechanical engineering community in the USA and abroad. He has published over 100 technical articles and chapters in journals and books and in 1971 and 1991 received the best paper award of ASME Lubrication Division.
Herbert Cheng has served effectively as a leader, advocator and implementer of community projects, sponsored by the American Society of Mechanical Engineers and the Society of Tribologists and Lubrication Engineers, aimed at transferring the results of tribological research to engineers and designers in industry.
In 19876, he was elected to the National Academy of Engineering for his pioneering contributions to tribology. In the same year he became the recipient of the STLE National Award, and was also promoted to the Walter P Murphy Chair of Mechanical Engineering.
Acclaimed for his pioneering work, an outstanding tribologist and leader in his field, Professor Cheng is indeed a worthy recipient of Tribology’s highest honour: The Tribology Gold Medal for 1992.