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TTU News

Setting his work up for failure has placed Tennessee Tech University associate professor Chris Wilson at the top of his profession in fatigue and fracture mechanics. A recent recipient of the Keith J. Miller Young Investigator Award from the American Society for Testing and Materials, Wilson has been recognized for his significant contributions in a field where success is all about understanding failure.

“It is often easier to manufacture a product than to design a process that allows you to study what happens when there are flaws or errors in the manufacturing process that lead to mechanical failure” said Wilson. “In our research, we try to replicate what happens when there’s a bad day—knowing that materials are inherently flawed.”

The importance of this fracture and fatigue testing and analysis lies with the stakes involved. The materials in Wilson’s lab are often the types used in modern military aircraft, space shuttle construction and satellites where the loss of nearly one-of-a-kind hardware or the potential loss of life is in the balance.

One of Wilson’s graduate assistants, Richard Gregory, is currently studying controlled porosity in just such a material: graphite/epoxy composites.

“For specialized uses in the military or space exploration, the consequences of failure in these materials is high,” said Gregory. “To compare it to testing more ordinary materials, if you are driving at truck at 30 miles an hour and have a flat tire, you can usually control the vehicle and stop and change the tire. If you have a flat tire on a racecar going 200 mph, you’ve created a much more dangerous situation.

“In the graphite/epoxy composite we are testing, small voids can jeopardize strength and durability,” he said. “We need to be able to recreate the process in which the flaws occur so we can eliminate them.”

The recent NASA mission to Mars illustrates how using light-weight, damage-tolerant materials can open up research possibilities. Wilson, who previously worked at Marshall Space Flight Center, says space research is one of many areas where reducing weight while maintaining strength saves money.

“It’s in vogue to talk in terms of what transporting weight into space costs,” said Wilson. “Now it costs about $1,000 per pound, but the goal is to build vehicles and equipment with lighter materials and better fuel systems to reduce the cost to about $100 per pound.”

ASTM’s Young Investigator Award rewards a member’s significant contributions to fatigue and fracture mechanics research at an early stage in his/her professional career. The award reflects excellence in publications, presentations, standards development activities and potential.

Wilson serves ASTM’s Committee E08 on Fatigue and Fracture as task group chairperson for software validation. He is also the secretary for the research and education subcommittee. He and fellow TTU mechanical engineering professor Dale Wilson have been recognized for their commitment to expose their students to the broader community in their field through symposia and workshops.