Taking a close look at metal 3-D printing

In the wee hours of a Saturday morning, Carnegie Mellon University Professor of Materials Science and Engineering Tony Rollett and graduate students Ross Cunningham and Tugce Ozturk sit together in Sector 2 of the mile-wide Advanced Photon Source at the Argonne National Laboratory in Chicago, Illinois. In front of them is an enormous synchrotron x-ray machine, powerful enough to see through heavy metals down to miniscule detail—one millionth of a meter, roughly one hundredth of a human hai