“It was designed and directly laser sintered in aluminum,” they write. “Using generative design tools and new material research, we basically created a lightweight aluminum structure like foam that is engineered on a cellular level to address specific functional needs for different areas in the object.
"The solid cells in the design create structural strength and rigidity while the more open cells create material reduction and lightness, all within one printing technique.”
This video gives you a look at the process. Watching parts of the structure emerge from the powder bed reminds me a lot of watching film develop in a darkroom tray: