Speaker: Donald Brown, LANL
Program Description
The last decade has seen tremendous advances in the ability of X-rays and neutrons at large scale facilities to probe microstructure at unprecedented length and time scales under unique environments that simulate manufacturing conditions. Concurrently, manufacturing is undergoing a revolution as investments are made in advanced manufacturing techniques, such as additive manufacture. It is natural that advanced manufacturing techniques should couple with advanced in-situ characterization techniques in order to accelerate the process of qualification of products for critical applications.
This talk will present our efforts to characterize the processing/microstructure/properties/performance relationship of additively manufactured materials across many length and time scales utilizing both neutron and high-energy x-ray scattering techniques. As an example of studying the effect of processing on microstructure, high energy x-ray diffraction has been used to monitor microstructural evolution in-situ during additive manufacture of 304L stainless steel with sub-second time resolution and sub 0.1mm spatial resolution. Specifically, the evolution of phase fractions, liquid and multiple solid phases, is monitored immediately following deposition. On larger time and length scales, neutron diffraction has been used to monitor microstructural evolution in-situ during post-deposition heat treatment of stainless steel, an integral part of metal additive manufacture. The study is extended to include the linkage of processing to properties through in-situ neutron diffraction measurements during deformation of additively manufactured materials.
