3D打印技术【英文】.ppt

3D printers are not your average printer ? They bear little resemblance to todays document or photo printers, ? They can build objects from scratch — or rather, from a CAD or 3D scanner file — out of a variety of materials. ? ? A typical 3D printer is very much like an inkjet printer( 喷墨式打印机） operated from a computer ? It builds up a 3D model one layer at a time, from the bottom upward, by repeatedly printing over the same area. ? The printer creates a model over a period of hours by turning a 3D CAD drawing into lots of two-dimensional （二维） , cross-sectional layers ? Most 3D printers essentially works by extruding molten thermoplastics (mostly ABS) through a tiny nozzle that it moves around precisely under computer control. ? Is not necessarily need to print in 3D with plastic: in theory, you can print objects using any molten material that hardens and sets reasonably quickly ? ABS has a whiteish-yellow color in its raw form, but pigments can be added to make it virtually any color ? A new technique has been created that prints out artificial blood cells ? Designed by scientists at Germans Fraunhofer Institute