3D Printing: Inventive Manufacturing: Aditive Manufacturing
The term 3D printing 's origin sense is in reference to a process that deposits a binder material onto a powder bed with inkjet printer heads layer by layer. More recently, the term is being used in popular vernacular to encompass a wider variety of additive manufacturing techniques. United States and global Technical standards use the official term additive manufacturing for this broader sense. ISO/ASTM52900-15 defines seven categories …show more content…
Most CAD applications produce errors in output STL files: holes, faces normals, self-intersections, noise shells or manifold errors. A step in the STL generation known as "repair" fixes such problems in the original model. Generally STLs that have been produced from a model obtained through 3D scanning often have more of these errors. This is due to how 3D scanning works-as it is often by point to point acquisition, reconstruction will include errors in most cases.
Once completed, the STL file needs to be processed by a piece of software called a "slicer," which converts the model into a series of thin layers and produces a G-code file containing instructions tailored to a specific type of 3D printer . This G-code file can then be printed with 3D printing client software .
Printer resolution describes layer thickness and X-Y resolution in dots per inch or micrometers . Typical layer thickness is around, although some machines can print layers as thin as .
Seemingly paradoxically, more complex objects can be cheaper for 3D printing production than less complex objects. …show more content…
The laser beam typically travels through the center of the deposition head and is focused to a small spot by one or more lenses. The build occurs on a X-Y table which is driven by a tool path created from a digital model to fabricate an object layer by layer. The deposition head is moved up vertically as each layer is completed. Metal powder is delivered and distributed around the circumference of the head or can be split by an internal manifold and delivered through nozzles arranged in various configurations around the deposition head. A hermetically sealed chamber filled with inert gas or a local inert shroud gas is often used to shield the melt pool from atmospheric oxygen for better control of material properties. The powder fed directed energy process is similar to Selective Laser Sintering, but the metal powder is applied only where material is being added to the part at that moment. The process supports a wide range of materials including titanium, stainless steel, aluminum, and other specialty materials as well as composites and functionally graded material. The process can not only fully build new metal parts but can also add material to existing parts for example for coatings, repair, and hybrid manufacturing applications. LENS, which was developed by Sandia National Labs, is one example of the Powder Fed - Directed Energy Deposition