Size & Shape Characterization of Metallic Powder for AM Through Novel Techniques

About the Course

Please join Dr. Edward Garboczi on Tuesday, February 20, 2018, at 2:00 pm Eastern time for this one hour webinar.

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, including the number of multi-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 particle shape will influence all the common particle size measurement techniques. This seminar will give an introduction to how particle shape and size characterization of metallic powders can be accurately performed in three dimensions (3D) using a combination of X-ray tomography and mathematical analysis. This 3D data can serve as "ground truth" with which to critically evaluate other methods for particle size and shape analysis.

Learning Outcomes

A webinar participant will be introduced to:

• How a combination of X-ray computed tomography (CT) and mathematical analysis gives the three-dimensional size and shape characterization of metallic additive manufacturing powder
• A brief introduction to the steps to this process, including sample preparation, X-ray CT, and types of mathematical analysis
• How particle shape influences the usual particle size measurements
• What can be learned, using these results, about powder shape and the frequency of multi-particles (two or more particles joined together) for virgin and recycled powders
• How these results can give insight into the physical characteristics of the powder-bed laser fusion additive manufacturing process

Registering for the Webinar

The fee is $89 per person. After registering you will receive an email within a few hours with information about how to access the webinar. In addition to the webinar, you'll get 7-day access to a recording of the webinar.

About the Instructors

Dr. Garboczi received his Ph.D. in Condensed Matter Physics from Michigan State University in 1985. His main research at NIST (Gaithersburg, Maryland) starting in 1988 was on the computational materials science of concrete and other composite materials, which later included carbon nanotube and graphene composites. This involves exploring relationships between microstructure and properties, at a number of length scales, using realistic computer-based microstructural models, exact property calculation algorithms, and percolation and composite theory. Driven by the needs of the computational materials science of concrete, since 2001 he has also used a novel 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, blast furnace slag, simulated and real lunar soil, chemical explosives, and powder for additive manufacturing. In 2014, he transferred to the Boulder, Colorado NIST campus, working on the same kind of problems but for a wider range of materials. Dr. Garboczi has published over 160 journal papers and is a NIST Fellow, and 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 2009 Edward C. Henry award from the American Ceramic Society's Electronics Division, 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.

Justin Whiting is a mechanical engineer research scientist at NIST focused on measurement science for additive manufacturing. He has more than five years' experience in the field of additive manufacturing research involving calorimetry of the directed energy deposition (DED) process, NDE of AM parts both in situ and post-process, characterization of precursor AM materials, and AM machine design. Justin began his research career monitoring micro-end mill tool wear using acoustic emission (AE) under a DARPA project at Northern Illinois University. This evolved into work led by Justin that implemented AE systems to monitor the multi-phase fluid flow in the powder fed DED process. Since then, Justin has focused his research on the study of metal AM precursor materials. His recent work at NIST has included characterization of particle size and morphology, spreadability and rheology, and the thermal properties of metal powders. Justin has been active in the AM standards community serving as chair of multiple America Makes & ANSI Additive Manufacturing Standardization Collaborative (AMSC) groups and convenor of an ISO-ASTM joint working group focused on Test Methods for the Characterization of Powder Flow Properties for Additive Manufacturing Applications

Stock #

TPTMETPOWDERWEBINAR0117