CALIFORNIA: Nexa3D, a leader in ultrafast 3D printing, has announced its intention to buy Essentium, a maker of high-speed extrusion 3D printers and materials for aerospace, military, and defense applications. The deal, which is subject to certain conditions, would add high-speed extrusion (HSE) technology to Nexa3D’s product range. Nexa3D and Essentium aim to create a…