Types of 3D Printing Technologies and Processes
1.Vat Photopolymerisation
a.Stereo lithography (SLA)
b.Digital Light Processing (DLP)
c.Continuous Liquid Interface Production (CLIP)
2.Material Jetting
3.Binder Jetting
4.Material Extrusion
a. Fused Deposition Modeling (FDM)
5.Powder Bed Fusion
a.Selective Laser Sintering (SLS)
b.Multi Jet Fusion (MJF)
c.Direct Metal Laser Sintering (DMLS)
6.Sheet Lamination
7.Directed Energy Deposition
1.Vat Photopolymerisation
A 3D printer based on the Vat Photopolymerizations method has a container filled with photopolymer resin. The resin is hardened with a UV light source.
Vat photopolymerisation (VP) is a versatile 3D printing process that uses light—typically ultraviolet (UV)—to selectively cure and harden liquid photosensitive resin in a vat, building objects layer by layer. It is widely recognized for producing parts with exceptional detail, high resolution (down to 10 microns in industrial systems), and smooth surface finishes, making it a preferred choice for intricate prototypes, dental models, and jewelry
Stereo lithography (SLA)
Stereolithography (SLA) is a type of 3D printing technology that uses a UV laser to turn liquid resin into solid plastic. It was the world's first 3D printing technology, patented in the 1980s.
Here is a breakdown of how it works and why it is used:
SLA 3D printing is commonly used for functional prototypes, cosmetic models, molds, and low-volume production parts that require fine features and clean surface quality. Because it can replicate intricate geometries and polished finishes, SLA is often chosen as an alternative to injection molding for prototyping and short-run manufacturing, especially when tooling costs and long lead times need to be avoided.
How it Works
- The Tank: The printer has a tank (vat) filled with liquid photopolymer resin (a plastic that reacts to light).
- The Laser: A UV laser traces the shape of a single layer onto the surface of the resin.
- The Cure: Where the laser hits, the liquid instantly "cures" (hardens) into a solid layer.
- The Build: The build platform moves up (or down), and the laser traces the next layer on top of the previous one until the object is finished.
Key Features
- High Precision: SLA is known for incredible detail and very thin layers, making it much smoother than standard FDM (filament) printers.
- Smooth Finish: The layers are so thin that they are often invisible to the naked eye.
- Common Uses: It is widely used for jewelry design, dental models (like clear aligners), and intricate prototypes.
Post-Processing
Unlike some other types of printing, SLA parts require extra steps:
- Washing: Parts must be rinsed in alcohol (IPA) to remove sticky leftover resin.
- Curing: Parts are often placed in a UV "oven" to fully harden and reach their maximum strength.