Cavalry scouts with the 1st Battalion, 16th Infantry Regiment, 1st Armored Brigade Combat Team, 1st Infantry Division maneuver toward cover after an air assault during Platinum Lion 19 at Novo Selo Training Area, July 9, 2019 Army researchers have devised a method to produce ceramic body armor, lightweight but strong, from a 3D printer. Except that 3D printers are meant to print out knickknacks, not flak jackets — which meant that engineers had to hack into the printer to get the job done. Ceramic armor, light but hard, provides great protection but can also be difficult to manufacture, notably in combining materials to create a strong com composite. “For ceramics, that’s a bit of a challenge because with you can’t really do a one-step additive manufacturing process like you could if a metal or a polymer,” said Lionel Vargas-Gonzalez, a researcher at the Army Research Laboratory. Ceramic armor stops bullets by shattering them or reducing their penetrative ability, but this depends on how porous the ceramic is. Ceramic armor can achieve “something that’s about 99 to 100 percent fully dense,” Vargas-Gonzalez said, and that density is impor...