Our team pioneered a custom biaxial load frame that allows us to fully explore the effects of multidirectional loading. It can produce arbitrary biaxial loading (tension-tension, tension-compression, and compression-compression) to accurately replicate the widest range of in-service loading conditions. Our one-of-a-kind transportable load frame is capable of mounting to a 6-axis translation + rotation stage in a high-energy X-ray beam line, and of being rotated through +/-180 degrees for purposes of high-energy diffraction microscopy. The design and build of this experiment took two years of development efforts by MTS engineers, our lab, and the scientists and engineers that support the 1-ID beam line at the Advanced Photon Source (APS) of Argonne National Laboratory. We ran our first in situ diffraction experiments at APS with this load frame in 2015.
The animation below, made by our postdoc Harshad Paranjape, shows the general configuration of the in situ experiment: X-ray tube, stereo digital image correlation cameras, load frame and detector.