Recognized for his undergraduate research project and paper entitled, “Patterned microtexture to reduce friction in prosthetic hip joints,” mechanical engineering masters candidate Anthony Chyr won the prestigious international E. Richard Booser Presidential Award (for undergraduate students) of the Society of Tribologists and Lubrication Engineers (STLE) for 2013. Chyr’s paper was recently published in the International Tribology and Lubrication Technology Magazine.

Founded in 1944, STLE is the premier technical society serving the needs of more than 10,000 individuals and 150 companies and organizations that comprise the tribology and lubrication engineering business sector. STLE members are technical experts who research, develop and market the methods and products that make industry more successful and that enhance the well being of people worldwide.

Advised by mechanical engineering assistant professor Bart Raeymaekers, Anthony’s research addresses increasing the longevity of prosthetic hip joints. There are approximately 285,000 total hip replacement surgeries performed in the U.S. each year. Most prosthetic hip joints begin to fail after 15 years of use, primarily due to wear and wear debris incited disease.

Chyr’s work is to increase the durability of hip joints by creating a patterned microtexture that reduces friction in the prosthetic hip joint by increasing the lubricant film thickness. Research results indicate that the microtextured specimen outperforms the benchmark smooth specimen in two ways. First, the friction coefficient is lower for the microtextured compared to the smooth cylinder over almost the entire kinematic cycle, indicating that friction is reduced significantly.

Second, the friction coefficient for the microtextured specimen experiences a sharp drop surrounding direction reversals. In contrast, the friction coefficient for the smooth specimen decreases slowly after direction reversals. This indicates that solid-on-solid contact between the surfaces is reduced for the textured versus the smooth. This could lead to reduced wear and correspondingly, increased longevity.

Daily human joint activity includes frequent starts and stops, and it is during these periods of high-friction boundary lubrication that the most wear occurs. Thus, the microtexture reduces friction and wear precisely at instants where it is needed most.

Anthony Chyr received his bachelors of science in 2013 from the University of Utah and is a member of the Nano-Tribology and Precision Engineering Laboratory directed by Dr. Bart Raeymaekers. The Department of Mechanical Engineering at the University of Utah is committed to providing students with broad-based, rigorous and progressive education. By combining state-of-the-art facilities with renowned faculty, the department provides an education that gives students the necessary skills to become the next generation of innovators.

A Chyr and B Raeymaekers, “Patterned microtexture to reduce friction in prosthetic hip joints,” Tribology and Lubrication Technology Magazine, April 2014.