7 Types of 3D Printers to Know

3D printing is a form of additive manufacturing in which three-dimensional objects are constructed layer by layer according to computer-aided design data. During this process, materials are fused together through a number of wide-ranging techniques — melting, sintering, curing, adhesive bonding and so on — in order to rapidly create iterative, tailor-made prints with total design freedom in a matter of hours.

Today, the International Organization for Standardization defines all existing 3D printing methods under seven different categories, distinguished by the way in which layers of material are created. Given that this technology has only been around since the 1980s, new types are likely to develop in the near future as leaders continue to innovate this space.

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Types of 3D Printing

Material Extrusion

Material extrusion (MEX) is the most common 3D printing method. It melts mixed filaments, typically thermoplastics, as they extrude through a heated nozzle attached to a robotic arm. These printheads move along a predefined path as instructed by a CAD file, depositing molten material on top of previous layers as they cool, cure and solidify. Layer by layer, this process repeats in a continuous stream until the desired structure is formed. Material extrusion is popular among hobbyists as it’s user-friendly, doesn’t come with a steep learning curve and is relatively inexpensive after upfront costs.

• Material extrusion methods: Fused deposition modeling, fused filament fabrication, composite filament fabrication
• Use cases: Prototyping, proof-of-concept modeling, manufacturing, building houses, engineering food products, temporary machine parts, bioprinting organs

Binder Jetting

Binder jetting (BJT) constructs three-dimensional objects by binding powdered materials — such as metal, sand or ceramics — with a liquid bonding agent. As thin layers of powder are spread across a build tray, a print head zips across x, y and z axes, selectively depositing an adhesive substance according to a CAD model. This glue binds the particles together — no heat or light source required. Binder jetting’s ability to turn out high-volume production makes it a competitor to traditional manufacturing practices. It’s also known for printing prototypes and large-scale parts at high speeds and low cost.

• Binder jetting methods: Furan binder, silicate binder, phenolic binder, aqueous-based binder
• Use cases: Prototyping, manufacturing, aerospace and automotive engine components, medical implants, dental products, colorful architectural models, casting molds, packaging, toys, figurines

Direct Energy Deposition

Directed energy deposition (DED) uses a focused thermal energy source — such as a laser, plasma arc or electron beam — to melt and fuse materials together as they are being deposited. These systems feature a multi-axis robotic arm that can deposit molten powder or wire at any angle, making directed energy deposition useful for performing repairs or adding material to existing components. Typically, this technique is performed within a controlled chamber or vacuum at reduced oxygen levels. Since DED prints are only limited by the reach of the robotic arm, this method is used to work on large-scale projects of near-net shape. 

• Direct energy deposition methods: Laser engineering mesh formation, directional light production, direct metal deposition, 3D laser coating
• Use cases: Repairing existing, high-value structures such as satellites, military aircraft components and turbine blades

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Material Jetting

Material jetting (MJT) builds three-dimensional objects one droplet at a time. This method shares likeness with your average office inkjet printer, featuring an oscillating printhead that swings back and forth across a build tray. But instead of ink, material jetting printers deposit drops of liquid photopolymer resin. Each layer cures under a UV light that is applied immediately after deposition, forming a solid object. Material jetting is the only additive manufacturing method capable of mixing resins in a single print.

• Material jetting methods: PolyJet printers, nanoparticle jetting, drop-on demand
• Use cases: Prototyping, industrial tooling, jewelry casting patterns, anatomically accurate medical models

Powder Bed Fusion

Powder bed fusion (PBF) selectively joins powder particles using a heat source, typically a laser. As each cross section is fused together, a recoater blade covers the build platform with a fresh layer of powder, repeating this process until the entire object is fabricated. This 3D printing technique is a relatively high-cost method of additive manufacturing that’s known to create high-precision structures with fine details and intricate geometries. Parts made from powder-bed infusion tend to display exceptional weight distribution and dimensional accuracy, resulting in extraordinary mechanical properties that are otherwise unobtainable via traditional manufacturing methods. Because of these qualities, it’s most often used in industrial and commercial applications.

• Powder bed fusion methods: Direct metal laser melting, direct metal laser sintering, electron beam melting, selective laser sintering, selective heat sintering, multi jet fusion
• Use cases: Prototyping, end-use production, tooling, custom manufacturing, aircraft and automotive parts, orthopedic implants

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Sheet Lamination

Sheet lamination (SL or SHL) bonds sheet stacks together to create three-dimensional objects. These thin layers of paper, plastic, ceramic, polymer or metal foil are joined using a variety of methods — either welding, heat, pressure or a type of adhesive. Guided by a CAD file, a laser, blade or cutting tool cuts shapes into each new layer that’s distributed by a feedstock roller over a descending build platform. Excess materials — which acts as a structural support in the meantime — are cut away to shape the object’s final form, and recycled for the next project. SL is the only additive manufacturing technique that can construct metal prints at low temperatures, and is often used to create colored objects in high resolution. 

• Sheet lamination methods: Ultrasonic additive manufacturing, selective deposits layer, laminated object manufacturing
• Use cases: hybrid manufacturing, ergonomic studies in product development, topography visualization, paper-based architecture models, functional and lightweight aerospace and automotive parts

Vat Polymerization

Vat polymerization (VPP) uses UV light to turn liquid photopolymers into solid structures. These pieces are typically constructed upside down, where a build platform lowers into a vat of resin. A UV light, directed and intensified with mirrors, cures the resin onto the build platform layer by layer until the print is complete. VPP is known for creating high resolution prints that are unmatched in accuracy, complete with fine details and smooth surfaces. As one of the only biocompatible 3D printing methods, it’s commonly used to create orthodontic models, like dentures and retainers, as well as hearing aids and facial prosthetics. 

• Vat polymerization methods: Stereolithography, digital light processing, liquid crystal display
• Use cases: Prototyping, patterns, molds, tooling, dental applications, medical-grade prosthetics and surgical guides, jewelry casting, model making

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