Additive Manufacturing (AM): the process and technologies utilized to create three-dimensional (3D) objects by building the object layer-by-layer with a desired material. This material (plastic, metal, and much more...) is ADDED in this layer fashion instead of the more commonly and older technologies of subtractive manufacturing such as milling, routing, machining, carving, etc. where material is removed from a stock shape to create the desired object. |
A disruptive technology that can be considered a major innovative complement to currently existing production technologies and where the design and application possibilities are almost limitless! |
Overview of AM Technologies
AM is a difficult process to categorize and introduce, as the number of different technologies that are considered AM are myriad and are growing exponentially very quickly. Even within what are considered the major categories, there are many different variations, some with only minute differences, but others with major modifications and innovative updates. Additionally, as such a new field of innovation, many have and are creating hybrid versions where multiple AM technologies are being combined into one process.
| Major AM Category | Non-Exhaustive List of Included Technologies | Brief Description | Material Feedstock Form | Energy Used for Material Consolidation | |
|---|---|---|---|---|---|
| Material Extrusion | Fused Filament Fabrication (FFF) | Deposit of thermoplastic filament in a layer-by-layer fashion through thermal extrusion |
| Filament | Thermal (sometimes additional UV or Laser) |
| Fused Deposition Modeling (FDM) | Same process as FFF, but FDM is a trademarked term | Filament | Thermal (sometimes additional UV or Laser) | ||
| Continuous Fiber (CF3D) | Use of continuous fiber reinforcement (either incorporated into the thermoplastic resin or applied separately) in order to gain additional mechanical reinforcement through specific designs | Continuous Fiber-Reinforced Filament | Thermal (sometimes additional UV or Laser) | ||
| Powder Bed Fusion | Selective Laser Sintering (SLS) | Application of layers of powder that are sequentially exposed to a laser that melts the current layer design. The laser penetrates multiple layers of powder to adhere the various layers together as the print progresses |
| Powder | Thermal and Directed Laser |
| Multi-Jet Fusion (MJF) | Use of ultraviolet (UV) energy and specific application of UV-absorbing fusing agents to create thermal energy high enough to melt sequentially applied layers of powder |
| Powder with Liquid Additives (Spray) | Thermal and UV | |
| Vat Polymerization | Stereolithography (SLA) | Curing of photopolymer resin in a vat via the application of a laser |
| Liquid | Directed Laser |
| Digital Light Processing (DLP) | Similar to SLA, but exposing the entire layer at once to the laser source | Liquid | Laser | ||
| Continuous Liquid Interface Production (CLIP) or Continuous Digital Light Processing (CDLP) | Similar to SLA, but utilizing a film/liquid interface to make the process continuous and faster than traditional SLA | Liquid | Laser | ||
| PolyJet | Application of a curable photopolymer resin (followed by curing) directly onto a print bed one layer at a time |
| Liquid | Laser | |
| Jetting | Material Jetting | Spraying of photocurable liquid droplets onto a print platform. After application of UV energy, the droplets are cured, allowing for the next layer to be subsequently sprayed |
| Liquid Spray | UV |
| Binder Jetting | Use of a sprayed binder materials (photocurable) to "glue" powder particles together, layer-by-layer, into the designed part |
| Powder with Liquid Additives (Spray) | UV | |
| Composite Hybrid Techniques | Additive Fusion Technology (AFT) | Hybrid filament process where continuous fiber-reinforced filament is printed into the designed object. The object is then exposed to high pressure and heat to completely consolidate the layers and remove any voids | Various | Thermal and Pressure | |
| Sheet Lamination | Use of applied polymer powder or films to reinforcing fabric sheets. These composite fabrics are then exposed to either thermal energy or a laser to melt the polymer, consolidating it with the fabric. Following this, the individual layers are cut from the fabric, applied layer-by-layer to assemble the final part, and then exposed to heat and pressure to consolidate the layers |
| Various | Thermal and Pressure | |
