3D printing, also known as additive manufacturing, is a general term for the process of manufacturing parts or physical objects through material stacking based on three-dimensional model data. It covers several completely different 3D printing processes. These 3D printing technologies are vastly different, but the key processes are the same. For example, all 3D printing starts with digital models because the technology is essentially digital. Parts or products are initially designed using computer-aided design (CAD) software or obtained as electronic files from a digital parts library. Then, the design file is decomposed into slices or layers using special construction software, generating path instructions for the 3D printer to follow， to conduct 3D printing.
There are many ways to classify these 3D printing technologies, among which the most common and typical classification method is the 7 mainstream classifications of 3D printing based on the ISO:
1. Material extrusion:
Squeezing melted thermoplastic through a heating nozzle (3D printing filament) , place the material on the construction platform, cool and solidify to form a solid object. Including fused deposition modeling (FDM), architectural 3D printing, micro 3D printing, biological 3D printing, and more. This technology has a low cost and a wide range of materials, providing the possibility for many small innovative projects and individual enthusiasts to realize their creativity. For example, in households, people can use material extrusion 3D printers to print personalized phone cases, small ornaments, and so on. But its material properties are relatively low (strength, durability, etc.), and there are also certain limitations in terms of dimensional accuracy.
2.Restoration polymerization (Photocuring):
Resin 3D printing, using liquid photosensitive resin hardened by a light source, layer by layer curing to form a solid structure, including Stereo Lithography Appearance (SLA), Digital Light Processing (DLP), and Laser Cladding Deposition (LCD), etc. In the fields of jewelry manufacturing and dentistry, reduction polymerization technology can print extremely complex and intricate structures, such as customized jewelry and dental crowns.
3.Powder Bed Fusion (PBF):
Powder materials are sintered layer by layer into solid objects by fusing powder particles with high-energy sources. Unsintered powders can be used as support structures, including Selective Laser Sintering (SLS), Laser Powder Bed Fusion (LPBF), Electron Beam Melting (EBM), etc. This technology is often used in the aerospace industry to manufacture high-strength and high-precision components, as it can meet stringent performance requirements.
4.Material Jetting:
Spray small droplets of liquid photosensitive adhesive onto a powder bed, then cure with a light source and build the object layer by layer. It covers Material Jetting (MJ), Nano Particle Jetting (NPJ), etc. One application of this technology is to manufacture parts in multiple colors and textures, which has advantages in multi material printing and can produce complex components with multiple properties, suitable for automotive manufacturers, industrial design companies, art studios, hospitals, and other fields.
5.Binder Jetting:
spraying small droplets of liquid adhesive onto a bed of granular material, followed by sintering to solidify the material together, layer by layer stacking to form a solid, including metal Binder Jetting, polymer Binder Jetting, and sand Binder Jetting. Suitable for large-scale production, able to quickly manufacture a large number of identical components.
6.Directed Energy Deposition (DED):
Simultaneously depositing and fusing molten metal, stacking the molten metal layer by layer to form a solid object, including Laser Powder Directed Energy Deposition (LP-DED), wire Arc Additive Manufacturing (WAAM), Electron Beam Directed Energy Deposition(EB-DED) , Cold Spray,etc. It is one of the most widely used categories of 3D printing. This technology is considered a faster and cheaper manufacturing technique for small batch metal castings and forgings, as well as critical maintenance for applications in the offshore oil and gas industry, aerospace, power generation, and utilities. In the automotive industry, this technology can be used to manufacture high-performance engine components.
7.Laminated Object Manufacturing:
Stacking and laminating very thin material sheets together to produce a 3D object or stack, and then using mechanical or laser cutting to form the final shape of the 3D object, including Laminated Object Manufacturing(LOM), Ultrasonic Consolidation(UC), Viscous Lithography Manufacturing (VLM), Composite Based Additive Manufacturing (CBAM), Selective Lamination Composite Object Manufacturing (SLCOM), etc. Although it may not be as fast and accurate as some other technologies, it also has unique value in certain specific application scenarios, such as the manufacturing of large sheets.
The classification of 3D printing technology is rich and diverse. In addition to the seven most common categories of 3D printing technology mentioned above, there are many other types of 3D printing technology, each of which has its unique advantages and scope of application. With the continuous advancement and innovation of technology, we believe that these 3D printing technologies will demonstrate strong potential in more fields and create a more exciting future for us.