Author: Ashley Spear

Ph.D. student, Dillon Watring, recently published his work on the effect of additive manufacturing parameters on the fatigue-driving mechanisms in AM IN718.  Dillon and his collaborators found that build orientation is linked to surface roughness, which is, in turn, linked to fatigue life.  For a given build orientation, there is an optimal range of laser-energy density; outside of this range, internal defects like lack-of-fusion and secondary cracking lead to reductions in total fatigue life.  To read more, check out the complete manuscript. This work is supported by an NSF CAREER award (CMMI-1752400) and by the DOD Office of Economic...

MMM Lab members, Kyle Pierson and Dr. Aowabin Rahman, implemented a convolutional neural network to predict the growth of a 3D crack surface and to quantify the corresponding model uncertainty. The work was supported by the Air Force Office of Scientific Research Young Investigator Program under Agreement No. FA9550-15-1-0172. Click here to access the full article....

What is the minimum volume requirement for specimens and models to guarantee representative behavior of microstructurally small cracks? Ph.D. student and NDSEG Fellow, Karen DeMille, recently published a paper in Engineering Fracture Mechanics that seeks to answer this very question.  She found that the answer depends upon the microstructural arrangement near the crack front as well as the boundary conditions. Her work provides a closed-form approximation for experimentalists and modelers to quickly estimate, under certain assumptions, how much volume would be needed to guarantee that crack-front fields are converged and therefore representative of a crack in a larger structure....

Dr. Joe Tucker (Exponent) and Prof. Spear published a paper recently in the journal Integrating Materials & Manufacturing Innovation (IMMI) that describes a new capability in the widely used software DREAM.3D that allows for generating open-cell, polycrystalline metallic foams. The new capability allows users to generate completely synthetic polycrystalline foam structures, or to overlay synthetic grain structures onto 3D image data of real open-cell foams (for example, from X-ray CT).  The plug-in will soon be available free to the public.  To read more, click here. The work will appear in a thematic issue of IMMI on 3D Materials Science and is supported by...