“Additive manufacturing” (AM) describes the use of 3D printing to make functional components, including tools and end-use production parts. Unlike “subtractive manufacturing” processes such as machining, where parts are created by removing material, additive manufacturing builds geometries by “adding” feedstock such as filament, wire or powder.
Depending on the 3D printing process and application, additive manufacturing can utilize a growing catalog of materials including metal alloys, thermoplastics, thermoset polymers and composites.
Even though it is newer than other manufacturing processes, AM is arguably the broadest category of manufacturing we have. While it first gained traction for production in the aerospace and medical industries, AM is now being applied to an ever-expanding collection of end markets including automotive, dental, heavy equipment, oil and gas, rail, marine, and even consumer goods.
Compared to subtractive processes like milling, additive manufacturing generally provides greater geometric freedoms and utilizes less material. In contrast to forming processes such as injection molding or composites layup, 3D printing does not require a mold or other tooling to create a part.
Additive manufacturing has been shown to be a good option in production applications where long lead times or associated costs preclude the use of expensive tooling; complexity of geometry is advantageous; and/or low volumes are required, though the quantities appropriate for 3D printing continue to increase.
Is Additive Manufacturing the Same as 3D Printing?
Some say yes and we say no! AM and 3D printing are overlapping terms but not synonyms. 3D printing is the operation at the heart of additive manufacturing, just as “turning” or “molding” might be the operation at the heart of a conventional manufacturing process.
In a nutshell, 3D printing is one step in an overall additive manufacturing workflow that also includes design, build preparation, postprocessing, business considerations and more.
Importantly, “3D printing” does not describe just one type of technology. Per ISO/ASTM, there are seven different “families” of 3D printing processes, and a growing number of material and machine options.
Why Use Additive Manufacturing?
Some associate AM with prototyping, but this is outdated. 3D printing has become well-established as a means of creating tooling for a range of conventional processes. And, manufacturers are increasingly adopting AM for production, including full-scale production.
However, the parts produced additively generally are not parts we recognize. The best candidates for AM are new components realizing new ideas that couldn’t have been made any other way. 3D printing provides geometric complexity “for free” which makes it possible to consolidate, lightweight and otherwise improve on the designs of many conventionally made parts and assemblies.
Introduce some processes of additive manufacturing
Additive manufacturing is the process of applying 3D-printing to industrial production that allows materials to be created without joints and with minimal post-processing. Multiple materials can be used during this process, which makes it easy to create new products with minimal waste and lower materials costs.
There are seven additive manufacturing production techniques. Each vary due to materials, layering, and machine technology needed. we specializes in all seven, and can help your team identify, design and implement the process that’s right for your application.
1) Powder Bed Fusion
This type of additive manufacturing uses either a laser or electron beam to melt and fuse material powder together to develop products. Here are the differences between the two types of powder bed fusion :
Laser Powder Bed Fusion – In laser powder bed fusion, a laser is used to heat material in a powder form into 3D products. After a layer of powder has been indexed down, a new layer of powder is spread to continue the process. Ultimately, laser powder bed fusion does not require support. Electron Beam Powder Bed Fusion – This type of powder bed fusion is used to melt particles together in specific areas. The beam can be manipulated very fast, which speeds the overall process by allowing multiple melt pools to occur simultaneously.
2) Directed Energy Deposition
In directed energy deposition (DED), powder or metal wire is used with an energy source to add material or fuse a material onto an existing part or to create a new part. The process is generally used in large-scale additive manufacturing. Here are the three types of directed energy deposition:
Laser DED – Laser DED deposits powder onto the build while being melted by the laser at the same time. This process can generate much faster build rates over conventional laser powder bed fusion.
Arc DED (also known as wire arc additive manufacturing or WAAM) – An EWI specialty that is more dynamic than other additive manufacturing processes. Arc DED is suitable for large builds. An advantage for manufacturers is that existing arc-welding robots and power supplies.
Electron Beam DED – EB-DED enables the manufacturing of large parts extremely fast, which gives it an advantage over other types of additive manufacturing. The process is applied in industries such as heavy machinery, construction, mining, and aerospace to make large, low-volume parts.
3) Binder Jetting
Metal binder jetting additive manufacturing uses an ink-jet print head to print a binder onto the powder which “binds” the metal particles together into a green state. The parts are then removed from the powder bed and must go through a debinding and sintering process (in an oven) to make the parts fully dense and hard. Parts typically shrink 20-25% during the sintering process.
4) Sheet Lamination
This type of additive manufacturing binds sheets of material to form a part. There are two types of sheet lamination additive manufacturing:
Ultrasonic Additive Manufacturing – This type of sheet lamination uses ultrasonic vibrations to weld metal tapes together until it is able to form objects.
Friction Stir Welding – Using friction stir welding enhances material properties as each layer is stirred. This creates diffusion and reduces the grain size for a secure bond.
5) Material Extrusion
In material extrusion, a filament or thermoplastic material is used to create parts. With this process, the filament (or thermoplastic) is heated and then continuously layered through a nozzle to create the final product or part. New materials are available that have metal filler inside the plastic “rods” that are extruded. The parts then go through the debinding and sintering step like binder jetting to make metal parts.
6) Material Jetting
This additive manufacturing process New materials are available that have metal filler inside the plastic “rods” that are extruded. The parts then go through the debinding and sintering step like binder jetting to make metal parts.
7) Vat Photopolymerization
Unlike the other types of additive manufacturing, vat photopolymerization uses liquid resin. This photopolymer resin is applied layer by layer and then a UV light hardens the resin to create the final part or object.
The term “additive manufacturing” references technologies that grow three-dimensional objects one superfine layer at a time. Each successive layer bonds to the preceding layer of melted or partially melted material. Objects are digitally defined by computer-aided-design (CAD) software that is used to create .stl files that essentially “slice” the object into ultra-thin layers. This information guides the path of a nozzle or print head as it precisely deposits material upon the preceding layer. Or, a laser or electron beam selectively melts or partially melts in a bed of powdered material. As materials cool or are cured, they fuse together to form a three-dimensional object.
It may be something of a stretch to say that AM will ‘change the world,’ but it is already having a positive impact. It allows for the creation of complex design with less material wastage when compared to parts that require machining, as well as allowing for the creation of lighter structures. When these lighter structures are applied to aerospace or automotive applications, for example, they lead to fuel savings and the related environmental (and financial) benefits. AM also allows for the replacement of parts that may otherwise be impossible to replace, meaning that machines can be repaired rather than scrapped. In addition to these benefits, AM has also seen a level of democratisation in manufacturing, as more people set up domestic 3D printing stations to produce their own bespoke items.
Additive manufacturing is a specific 3D printing process. This process builds parts layer by layer by depositing material according to digital 3D design data. The term “3D printing” is increasingly used as a synonym for additive manufacturing. However, “additive manufacturing” better reflects the professional manufacturing process that differs significantly from conventional, subtractive manufacturing methods. For example, instead of milling a workpiece from a solid block, additive manufacturing builds the part up layer by layer from material supplied as a fine powder. Various metals, plastics and composite materials can be used.
Additive manufacturing is relevant in many areas and for numerous industries. Whether used for building visual and functional prototypes or small and medium series – and increasingly for series production. This method offers convincing advantages conventional methods cannot achieve. Product development and market entry can be significantly accelerated, agile product customization and functional integration can be achieved more quickly and at a lower cost. In this way, additive manufacturing gives large OEM manufacturers from a wide variety of industries the opportunity to differentiate themselves on the market in terms of customer benefits, cost reduction potential and sustainability targets.