Event Scheduled for Sep 29, 2017
Event: MSE Seminar Speaker - Dr. Ed Garboczi
Time: 09:45 am
Details of Event:
Dr. Ed Garboczi
NIST Fellow, Applied Chemicals and Materials Division, Material Measurement Laboratory, National Institute of Standards and Technology
Friday, September 29, 2017
Institute of Materials Science Building, Room 20, at 9:45 a.m.
Refreshments will be served at 9:30 a.m.
“Characterization of additive manufacturing metallic powder and pore structure using X-ray tomography”
Abstract: In the powder bed laser-melting process, metallic powder is systematically spread by a mechanical arm, a laser melts a pattern, and the process is repeated until the part is built. The shape and size of the powder particles affects the flow properties of the powder as it is spread, determines the density and thermal conductivity of the packed powder bed, and interacts strongly with the build process, since the lift in each cycle is usually less than the maximum powder size. But particle size measurements cannot be separated from particle shape, since shape will influence all the common particle size measurement techniques. In finished parts, even nominally fully dense parts have pores, and the pore structure must be determined to be consistent with design for higher porosity controlled-pore parts. This seminar will describe how particle shape and size characterization of metallic powders can be accurately done in 3D using a combination of X-ray tomography and spherical harmonic analysis. This 3D data can serve as “ground truth” with which to critically evaluate other 3D and 2D methods for particle size and shape analysis. Also using X-ray tomography to study pores in finished parts requires careful image segmentation, which will also be demonstrated.
Bio: Dr. Garboczi received his Ph.D. in Condensed Matter Physics from Michigan State University in 1985. His main research at NIST starting in 1988 was on the computational materials science of random composite materials such as concrete and other materials, using computer-based microstructural models, exact property calculation algorithms, and percolation and composite theory. Since 2000, he has also used a combination of X-ray computed tomography and spherical harmonic analysis to build quantitative mathematical models of random-shaped particles of cement, sand, gravel, fly ash, industrial mineral powders, and blast furnace slag, with other applications including simulated and real lunar soil, chemical explosives, and metallic powders for additive manufacturing. Dr. Garboczi is a Fellow of the American Ceramic Society and the American Concrete Institute. He received the Robert L' Hermite Medal from RILEM in 1992, a Silver Medal from the Department of Commerce in 2009, the 2012 Della Roy Lecture award from the American Ceramic Society’s Cements Division, and the 2014 Robert E. Philleo award from the American Concrete Institute.
Sponsored By: Materials Science and Engineering Department
Pamphlet/Flyer: No Pamphlet/Flyer Available