3D printing, also known as additive manufacturing (AM), is a process of creating three-dimensional objects by adding material layer by layer based on a digital model. Unlike traditional subtractive manufacturing (such as milling or cutting), 3D printing builds objects up from nothing, layer by layer, until the final product is complete.
- Basic Working Principle
The process starts with a 3D digital model (usually designed using CAD software), which is sliced into thin horizontal layers. The 3D printer reads this model and deposits material in each layer, solidifying it as it goes. After each layer is printed, the printer moves slightly to print the next layer, gradually building up the object.
- Main 3D Printing Technologies
SLA
SLA uses ultraviolet (UV) light to cure liquid resin, turning it solid layer by layer. The resin is carefully cured by a laser to form highly detailed and smooth objects.
A laser selectively hardens resin in thin layers.
Each layer is hardened before the next one is printed.
After printing, the object usually requires post-processing like cleaning and additional UV curing.
SLS
SLS uses a laser to selectively fuse powdered material, such as plastic, metal, or ceramic, to form each layer of the object. It works with both plastics and metals, and the process does not require support structures, which is beneficial for complex geometries.
A laser fuses the powder layer by layer.
The unfused powder remains as support material.
Once printing is done, the excess powder is removed, leaving the finished part.
SLM
SLM is similar to SLS but uses metal powders. It melts metal powders layer by layer using a laser, and it’s commonly used for creating metal parts in industries like aerospace and automotive.
SLM allows for high-performance metal parts that are precise and strong.
After printing, the parts are often heat-treated to achieve the desired mechanical properties.
DLP
DLP (Digital Light Processing) 3D printing is an additive manufacturing technology based on the principle of photopolymerization, which typically uses liquid resin and ultraviolet light to project and solidify the resin layer by layer, thus constructing a three-dimensional object. Compared to other photopolymerization technologies like SLA, the main feature of DLP printing is the use of a digital light source (such as a high-brightness digital projector) for printing.
In DLP printing, the slicing software divides the digital model into multiple thin layers, and each layer is projected by a light source.
3. Advantages of 3D Printing
High Design Freedom: 3D printing allows the production of complex shapes and structures that would be difficult or impossible with traditional manufacturing methods.
Rapid Prototyping: It allows quick iteration of design models and the creation of prototypes within hours or days, accelerating product development.
Customization: 3D printing is excellent for custom, personalized products like medical implants or unique consumer goods.
Material Efficiency: Since it’s an additive process, 3D printing uses only the material needed for the object, reducing waste compared to subtractive manufacturing.
Low-Cost Small-Scale Production: It’s ideal for producing low-volume, customized parts without the need for expensive molds or tooling.
