NASA researchers use X-ray imaging to observe heat shield degradation

Researchers from NASA, the University of Illinois Urbana-Champaign, and the Lawrence Berkeley National Laboratory have successfully captured real-time, three-dimensional views of spacecraft heat shield materials degrading under extreme heat. Using X-ray micro-computed tomography (micro-CT) at the Advanced Light Source, the team observed structural changes in ablative materials as they were heated to temperatures up to 1,652 degrees Fahrenheit.

This technique allows engineers to witness the process of ablation—where protective materials sacrifice their outer layers to absorb heat—as it occurs. Previously, engineers had to rely on observations made before and after testing because monitoring the microscopic breakdown during the heating process was exceptionally difficult. To improve image quality, the team utilized an AI method trained on high-resolution scans to enhance sequences of quicker scans.

The study focused on two specific materials, SLA-220 and SLA-561V, which are used on the backshells of spacecraft. These insights are expected to help engineers better predict heat shield performance for future missions, including those related to the Artemis program.