COLLABORATION IN BASIC SCIENCE AND ENGINEERING (COBASE)

Beginning in October 1999, Yuri Gogotsi hosted Ukrainian scientist Andriy Kovalchenko for one year. COBASE sponsored the first six-month period of their research, and thanks to their good results, they found another funder to cover the final six months. The primary scientific objective of the visit was to investigate phase transformation in silicon during friction under different friction conditions and to estimate its effect on the mechanism of wear. Another goal was to establish a working relationship between the University of Illinois at Chicago and the Institute for Problems of Materials Science in Kiev.

Dividing his time between the University of Illinois at Chicago and Argonne National Laboratory, Kovalchenko carried out tribological experiments using pin-on-disk friction machines to estimate friction characteristics of silicon during sliding against silicon nitride under conditions of boundary, limited and no lubrication. Following these tests, Kovalchenko investigated the worn surfaces of silicon by Raman spectroscopy and Scanning Electron Microscopy. He also performed surface analysis using an optical profilometer. From this research, Kovalchenko gained new insight into the transition of mechanisms of wear and different phase transformation depending on working conditions.

During his stay, Kovalchenko had the opportunity to report on his previous investigation of abrasive wear of ceramics at a UIC seminar. In July, he presented the preliminary results of his most recent work at the Gordon Conference on Tribology in Plymouth, NH. Currently, Gogotsi and Kovalchenko are preparing an article summarizing the results of their investigation of phase transformation during friction of silicon as well as a presentation of the materials on scientific conferences.