Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next generation gas turbine engines, but real-time analysis of the mechanical properties of these space-age materials at ultrahigh temperatures has been a challenge until now. Researchers with the U.S. Department of Energy (DOE)'s Lawrence Berkeley National Laboratory (Berkeley Lab) have developed the first testing facility that enables CT-scanning of ceramic composites under controlled loads at ultrahigh temperatures and in real-time.
Working at Berkeley Lab's Advanced Light Source (ALS), a premier source of X-ray and ultraviolet light beams, the scientists created a mechanical testing rig for performing X-ray computed microtomography that reveals the growth of microcrack damage under loads at temperatures up to 1,750 degrees Celsius. This allows engineers to compute a ceramic composite material's risk of structural or mechanical failure under extreme operating conditions, which in turn should enable the material's performance and safety to be improved.
"The combination of our in situ ultrahigh temperature tensile test rig and the X-rays at ALS Beamline 8.3.2 allows us to obtain measurements of the mechanical properties of advanced ceramic materials at temperatures that are literally unprecedented," says Berkeley Lab materials scientist Robert Ritchie, who led this work. "These measurements, coupled with wonderful 3D images and quantitative data of the damage under load, can provide crucial information to permit accurate predictions of a ceramic composite's structural integrity and safe lifetime."
Ritchie, who holds joint appointments with Berkeley Lab's Materials Sciences Division and the University of California (UC) Berkeley's Materials Science and Engineering Department, is the corresponding author of a paper describing this work that has been published in the journal Nature Materials. The paper is title
|Contact: Lynn Yarris|
DOE/Lawrence Berkeley National Laboratory