Many outsiders think that 3D printing is simply extruding material from a hot nozzle and stacking it into shapes, but in fact, 3D printing is much more than that! The following will introduce seven major categories of 3D printing technologies, allowing even beginners to clearly distinguish between different 3D printing processes.
In fact, 3D printing, also known as additive manufacturing, is a general term that encompasses several distinctly different 3D printing processes. These technologies are worlds apart, but the key processes are the same. For example, all 3D printing starts with a digital model, as the technology is inherently digital. Parts or products are initially designed using computer-aided design (CAD) software or obtained from electronic files from a digital parts library. The design file is then sliced into layers for 3D printing using specialized build preparation software, generating path instructions for the 3D printer to follow. Next, you will learn about the differences between these technologies and the typical uses of each.Why seven types?The types of additive manufacturing can be categorized based on the products they produce or the types of materials used. The International Organization for Standardization (ISO) divides them into seven general types (though these seven categories of 3D printing are also difficult to cover the increasing number of technological subtypes and hybrid technologies):● Material Extrusion● Reduction Polymerization● Powder Bed Fusion● Material Jetting● Binder Jetting● Directed Energy Deposition● Sheet Lamination1. Material Extrusion
△ Material Extrusion 3D PrintingMaterial extrusion, as the name implies, involves extruding material through a nozzle. Typically, this material is a type of plastic filament, melted and extruded through a heated nozzle. The printer deposits the material onto the build platform along a process path obtained through software. The filament then cools and solidifies to form a solid object. This is the most common form of 3D printing. At first glance, this may sound simple, but considering the extruded materials, including plastics, metals, concrete, bio-gels, and various foods, this is actually a very broad category. The price of this type of 3D printer ranges from $100 to seven figures.● Subtypes of Material Extrusion: Fused Deposition Modeling (FDM), Construction 3D Printing, Micro 3D Printing, Bio 3D Printing● Materials: Plastics, Metals, Foods, Concrete, etc.● Dimensional Accuracy: ±0.5% (lower limit ±0.5mm)● Common Applications: Prototypes, Electrical Housings, Shape and Fit Testing, Jigs and Fixtures, Lost-Wax Casting Models, Houses, etc.● Advantages:Lowest-cost 3D printing method with a wide range of materials● Disadvantages: Typically lower material performance (strength, durability, etc.), usually not high dimensional accuracy1. Fused Deposition Modeling (FDM)
△ FDM Parts Can Be Made from Metal or Plastic on Various 3D PrintersFDM 3D printers are a multi-billion dollar market with thousands of machines, ranging from basic models to complex models from manufacturers. FDM machines are referred to as Fused Filament Fabrication (FFF), which is the same technology. Like all 3D printing technologies, FDM starts with a digital model and then translates it into a path that the 3D printer can follow. Using FDM, a filament from a spool (or several at once) is fed into the printer nozzle in the extrusion head. The printer nozzle or multiple nozzles are heated to the required temperature, softening the filament to connect continuous layers into a solid part.As the printer moves the extrusion head along specified coordinates on the XY plane, it continues to lay down the first layer. The extrusion head then rises to the next height (Z plane), repeating the process of printing the cross-section, layer by layer, until the object is fully formed. Depending on the geometry of the object, support structures may sometimes need to be added to support the model during printing, for example, if the model has steep overhanging sections. These supports are removed after printing. Some support structure materials can dissolve in water or another solution.
△ FDM 3D Printers Offer a Wide Range of Machines for Hobbyists, Small Businesses, and Manufacturers (Source: Creality, Raise3D, Stratasys)2. 3D Bioprinting
△ 3D Bioprinting is Similar to Traditional 3D Printing, but the Raw Materials Are Very Different3D bioprinting, or bio 3D printing, is an additive manufacturing process that combines organic or biological materials (such as live cells and nutrients) to create natural three-dimensional structures resembling tissues. In other words, bioprinting is a type of 3D printing that can produce anything from bone tissue and blood vessels to living tissues. It is used for various medical research and applications, including tissue engineering, drug testing and development, and innovative regenerative medicine therapies. The actual definition of 3D bioprinting is still evolving. Essentially, the working principle of 3D bioprinting is similar to FDM 3D printing and belongs to the material extrusion series (although extrusion is not the only method of bioprinting).3D bioprinting uses materials (bioinks) expelled from a needle to create printed layers. These materials, known as bioinks, mainly consist of living substances, such as cells in carrier materials—like collagen, gelatin, hyaluronic acid, silk, alginate, or nanocellulose, which serve as molecular scaffolds for structural growth and nutrients.3. Construction 3D Printing
△ Construction 3D PrintingConstruction 3D printing is a rapidly growing area of material extrusion. This technology involves using oversized 3D printers (often several meters high) to extrude construction materials like concrete from a nozzle. These machines often appear in the form of gantry or robotic arm systems. 3D construction printing technology is now used for residential buildings, architectural features, and construction projects ranging from wells to walls. Researchers claim it has the potential to significantly change the entire construction industry by reducing labor demands and minimizing construction waste.Dozens of 3D printed houses exist in the US and Europe, and research is underway to develop 3D construction technologies that will use materials found on the Moon and Mars to build habitats for future expeditions. Printing with local soil instead of concrete as a more sustainable building method is also being explored.2. Reduction Polymerization
△ Reduction Polymerization Using LaserBarrel polymerization (also known as resin 3D printing) is a series of 3D printing processes that use a light source to selectively cure (or harden) photosensitive polymer resin in a barrel. In other words, light precisely directs to specific points or areas of the liquid plastic to harden it. After the first layer is cured, the build platform moves up or down (depending on the printer) a small amount (usually between 0.01 and 0.05 mm), and the next layer cures, connecting with the previous layer. This process is repeated layer by layer until a 3D part is formed. After the 3D printing process is completed, the object is cleaned to remove any remaining liquid resin and post-cured (in sunlight or a UV chamber) to enhance the mechanical properties of the part.The three most common forms of barrel polymerization are Stereolithography (SLA), Digital Light Processing (DLP), and Liquid Crystal Display (LCD), also known as Mask Stereolithography (MSLA). The fundamental differences between these types of 3D printing technologies lie in the light source and how it is used to cure the resin.
△ Large Barrel Polymerization Utilizes Light to Cure Photosensitive Resin Layer by LayerSome 3D printer manufacturers, especially those that produce professional-grade 3D printers, have developed unique and patented variants of light polymerization, so you may see different technology names on the market. An industrial 3D printer manufacturer, Carbon, uses a barrel polymerization technology called Digital Light Synthesis (DLS), while Stratasys’s Origin refers to its technology as Programmable Photopolymerization (P3). Formlabs offers a technology known as Low Force Stereolithography (LFS), while Azul 3D is the first to commercialize a form of large area rapid printing (HARP) barrel polymerization. There are also light-based metal manufacturing (LMM), projection micro-stereolithography (PμSL), and Digital Composite Manufacturing (DCM), which is a photopolymer technology that introduces functional additives (such as metal and ceramic fibers) into liquid resin.● Types of 3D Printing Technologies: Stereolithography (SLA), Liquid Crystal Display (LCD), Digital Light Processing (DLP), Micro Stereolithography (μSLA), etc.● Materials: Photopolymer Resins (castable, clear, industrial, biocompatible, etc.)● Dimensional Accuracy: ±0.5% (lower limit ±0.15 mm or 5 nm, using μSLA)● Common Applications: Injection molding-like polymer prototypes and end-use parts, jewelry casting, dental applications, consumer goods● Advantages: Smooth surface finish, fine feature details1. Stereolithography (SLA)
△ Stereolithography (SLA) Examples from 3D Systems, DWS, and FormlabsSLA is the first 3D printing technology in the world. The stereolithography technology was invented by Chuck Hull in 1986, who patented the technology and founded 3D Systems to commercialize it. Today, this technology is available to enthusiasts and professionals from many 3D printer manufacturers. SLA uses a laser beam to target a vat of resin, selectively curing the cross-section of the object within the printing area, building layer by layer. While most SLA printers use solid-state lasers to cure parts, one drawback of this barrel polymerization is that point lasers may take longer to trace the cross-section of an object compared to the next method (DLP), which flashes light to immediately cure an entire layer. However, lasers can produce stronger light, which is necessary for certain engineering-grade resins.
△ SLA 3D Printers Use One or More Lasers to Trace and Cure a Single Layer of Resin at a TimeMicro Stereolithography (μSLA)Micro stereolithography technology can print miniature parts with resolutions between 2 micrometers (μm) and 50 micrometers. For reference, the average width of human hair is 75 micrometers. It is one of the “micro 3D printing” technologies. μSLA involves exposing a photosensitive material (liquid resin) to ultraviolet lasers. The difference lies in the specialized resin, the complexity of the laser, and the addition of lenses that produce nearly incredible small light spots.
△ Nanoscribe and Microlight3D are two leading manufacturers of TPP 3D printers (Source: Nanoscribe, Microlight3D)Two-Photon Polymerization (TPP)Another micro 3D printing technology, TPP (also known as 2PP), can be classified under SLA as it also uses lasers and photosensitive resins, but it can print parts smaller than μSLA, down to 0.1 microns. TPP uses pulsed femtosecond lasers focused on a narrow point within a large vat of special resin. This point then cures individual 3D pixels, also known as voxels, within the resin. These nano to micro-sized voxels are cured layer by layer along a predefined path. TPP is currently used for research, medical applications, and the manufacture of miniature parts, such as microelectrodes and optical sensors.
△ Micro 3D Printing: TPP Technology2. Digital Light Processing (DLP)
△ DLP 3D Printed Parts from Anycubic, Carbon, and ETECDLP 3D printing uses a digital light projector (instead of a laser) to flash each layer’s individual image (or multiple exposures for larger parts) simultaneously onto a layer of resin. DLP (more common than SLA) is used to produce larger parts or parts with larger volumes in a single batch because each layer exposure requires the same amount of time, making it more efficient than the point laser method in SLA. Each layer’s image consists of square pixels, resulting in a layer formed from small rectangular blocks known as voxels. Light is projected onto the resin using LED screens or UV light sources (lamps) and projected onto the build surface via digital micromirror devices (DMD).
△ Digital Light Processing (DLP) Resin 3D Printers Range from Hobbyist Versions to Full Manufacturing Production MachinesModern DLP projectors typically have thousands of micrometer-sized LEDs as light sources. Their switching states are individually controlled, allowing for improved XY resolution. Not all DLP 3D printers are the same; there are significant differences in the power of the light source, the lenses it passes through, the quality of the DMD, and many other components that make up a machine worth $300 compared to one worth over $200,000.Top-Down DLPSome DLP 3D printers have their light source mounted at the top of the printer, shining down onto the resin vat instead of shining upwards. These “top-down” machines flash an image layer from the top at once, curing one layer at a time, and then return the cured layer to the vat. Each time the build plate lowers, a recoater mounted at the top of the vat moves back and forth over the resin to smooth out the new layer. Manufacturers claim this method can produce more stable part outputs for larger print items, as the printing process does not fight against gravity. When printing from the bottom up, there are limits to how much weight can be suspended from the build plate. The resin vat also supports the printed parts during printing, reducing the need for support structures.
△ BMF’s MicroArch S230 Can Print Detailed Parts as Small as 2 Microns of Polymer or Ceramic (Source: BMF)Binder JettingBinder jetting is a 3D printing process in which liquid binder selectively bonds areas of a layer of powder. This type of technology combines characteristics of both powder bed fusion and material jetting. Similar to PBF, binder jetting uses powder materials (metal, plastic, ceramic, wood, sugar, etc.), and like material jetting, liquid binder polymers are deposited from the inkjet head. Regardless of whether the powder is metal, plastic, sand, or other materials, the binder jetting process is the same.First, a thin layer of powder is spread on the build platform by a recoater. Then, the print head, equipped with inkjet nozzles, passes over the bed, selectively depositing droplets of binder to bond the powder particles together. Once the layer is complete, the build platform moves down, and the blade recoats the surface. This process is repeated until the entire part is finished.The uniqueness of binder jetting lies in the absence of heat during the printing process. The binder acts as the glue that binds the polymer powders together. After printing, the parts are wrapped in unused powder, which usually remains to cure. The parts are then removed from the powder bed, and excess powder is collected and can be reused. From here, depending on the material, post-processing is required, except for sand, which can typically be used directly from the printer as cores or molds. When the powder is metal or ceramic, post-processing involving heating will melt the binder, leaving only the metal. Post-processing for plastic parts typically involves coatings to improve surface finish. You can also polish, paint, and sand polymer binder jetting parts.Binder jetting is fast and highly productive, allowing for economically efficient production of large quantities of parts compared to other AM methods. Metal binder jetting is popular for various metals in end-use consumer products, tools, and batch spare parts. However, the material choices for polymer binder jetting are limited, and the structural performance of the parts produced is lower. Its value lies in its ability to create full-color prototypes and models.● Subtypes of 3D Printing Technologies: Metal Binder Jetting, Polymer Binder Jetting, Sand Binder Jetting● Materials: Sand, Polymers, Metals, Ceramics, etc.● Dimensional Accuracy: ±0.2 mm (metal) or ±0.3 mm (sand)● Common Applications: Functional metal parts, full-color models, sand castings and molds● Advantages: Low cost, large build volume, functional metal parts, excellent color reproduction, fast printing speed, and flexibility in support-free designs● Disadvantages: A multi-step process for metals, polymer parts are not durable1. Metal Binder Jetting
△ Stainless Steel 3D Printed Parts Using Metal Jetting Technology by HPMetal binder jetting can also be used to create solid metal objects with complex geometries that far exceed the capabilities of traditional manufacturing techniques. Metal binder jetting is a highly attractive technology for batch production of metal parts and achieving lightweight designs. Since binder jetting can print parts with complex pattern fillings instead of solids, the resulting parts are significantly lighter while maintaining strength. The porosity characteristics of binder jetting can also be used to achieve lighter end parts for medical applications, such as implants.Overall, the material properties of metal binder jetting parts are comparable to those of metal parts produced by metal injection molding, making it one of the most widely used manufacturing methods for batch production of metal parts. Additionally, binder jetting parts exhibit higher surface smoothness, especially in internal channels.
△ Metal Binder Jetting 3D Printers Produce Fine Solid Metal Parts for End-Use ApplicationsMetal binder jetting parts require secondary processing after printing to achieve good mechanical properties. Freshly printed parts are basically made up of metal particles glued together with polymer binder. These so-called “green parts” are fragile and cannot be used as is. After the printed parts are removed from the metal powder bed (a process known as depowdering), they undergo thermal treatment in a furnace (a process known as sintering). Both printing parameters and sintering parameters are adjusted based on the geometry, materials, and desired density of specific parts. Sometimes bronze or other metals are used to infiltrate the voids in the binder jetting parts, achieving zero porosity.2. Polymer Binder Jetting
△ Polymer Binder JettingPolymer binder jetting is a process very similar to metal binder jetting as it also uses powder and liquid binder, but the applications are vastly different. After printing, polymer parts are removed from their powder bed and cleaned, typically ready for use without further processing, but these parts lack the strength and durability found in 3D printing processes. Polymer binder jetting parts can be filled with another material to increase strength. Using polymers for binder jetting allows for the production of multi-colored parts for medical modeling and product prototyping.3. Sand Binder Jetting
△ Sand Binder JettingSand binder jetting differs from polymer binder jetting in the printer and printing process, so it is distinguished here. One of the most common uses of binder jetting technology is to produce large sand casting molds, models, and cores. The low cost and speed of this process make it an excellent solution for foundries, as it is difficult to produce fine pattern designs in a matter of hours using traditional techniques.The industrial development future continuously places high demands on contract manufacturers and suppliers. Sand 3D printing is at the beginning of its potential. After printing, operators need to remove and clean the cores and molds from the build area to eliminate any loose sand. Molds can often be immediately prepared for casting. After casting, the molds are dismantled, and the final metal parts are removed.4. Multi Jet Fusion (MJF)
△ BASF and HP Collaborated to Develop a New Industrial-Grade Polypropylene for MJFAnother unique and brand-specific 3D printing process that does not easily fit into any existing category, and is not actually binder jetting, is HP’s Multi Jet Fusion. MJF is a polymer 3D printing technology that uses powder materials, liquid fusing agents, and detailing agents. It is not considered binder jetting because it adds heat to the process, resulting in parts with higher strength and durability, and the liquid is not entirely a binder. The process’s name comes from the multiple print heads executing the printing process.In the Multi Jet Fusion printing process, the printer lays down a layer of powder material, usually nylon, on the build bed. After this, the print heads pass over the powder and deposit fusing agents and detailing agents onto it. An infrared heating device moves over the printed item. Wherever the fusing agent is added, the lower layer melts together, while the areas with detailing agents remain powdery. The powdery parts fall away, creating the desired geometry. This also eliminates the need for modeling supports, as the lower layers support the layers printed above them. To complete the printing process, the entire powder bed and the printed parts within it are moved to a separate processing station, where most of the loose, unmelted powder is vacuumed and can be reused.Multi Jet Fusion is a versatile technology that has been applied across various industries, including automotive, healthcare, and consumer goods.
△ The HP Jet Fusion 5200 Series is One of Many Sizes and Styles of HP Multi Jet Fusion 3D Printers (Source: HP)6. Directed Energy DepositionDirected Energy Deposition (DED) is a 3D printing process where metal materials are melted while being deposited by a powerful energy source. This is one of the broadest categories of 3D printing, containing many subcategories depending on the form of the material (wire or powder) and the type of energy (laser, electron beam, arc, supersonic, heat, etc.). Essentially, it has many similarities with welding.This technology is used for layer-by-layer printing, often followed by CNC machining to achieve tighter tolerances. The combined use of DED and CNC is very common, with a subtype of 3D printing called hybrid 3D printing that includes both DED and CNC units within the same machine. This technology is considered a faster and cheaper alternative for small batch metal castings and forgings, as well as for critical repairs in offshore oil and gas industries and aerospace, power generation, and utility applications.
△ DED Metal 3D Printing Technology Can Quickly Create a Strong Metal Part That Can Then Be Machined to Strict Tolerances● Subtypes of Directed Energy Deposition: Powder Laser Energy Deposition, Wire Arc Additive Manufacturing (WAAM), Wire Electron Beam Energy Deposition, Cold Spray● Materials: Various metals, in wire and powder form● Dimensional Accuracy: ±0.1 mm● Common Applications: Repairing high-end automotive/aerospace components, functional prototypes, and end parts● Advantages: High deposition rate, ability to add metal to existing components● Disadvantages: Inability to make complex shapes due to the lack of support structures, usually poorer surface finish and precision1. Laser Directed Energy Deposition
△ 3D Printing Metal Using Laser and Powdered MetalLaser Directed Energy Deposition (L-DED), also known as Laser Metal Deposition (LMD) or Laser Engineering Net Shaping (LENS), uses one or more nozzles to deliver metal powder or wire, which is melted by a powerful laser onto the build platform or metal part. As the nozzle and laser move or the part moves on a multi-axis turntable, the object is built layer by layer. The build speed is faster than powder bed fusion but results in reduced surface quality and significantly lower precision, often requiring extensive post-processing. Laser DED printers typically have sealed chambers filled with argon to avoid oxidation. They can also operate using only localized argon or nitrogen when dealing with less reactive metals.The metals commonly used in this process include stainless steel, titanium, and nickel alloys. This printing method is often used to repair high-end aerospace and automotive components, such as jet engine blades, but is also used for producing entire parts.
△ Meltio M450 Wire Feed Laser DED 3D Printer, Optomec LENS CS 600 Metal Powder Feed Laser DED 3D Printer, and DMG Mori Lasertec 65 DED Wire Feed Laser DED 3D Printer.2. Electron Beam Directed Energy Deposition
△ Electron Beam DED 3D PrintingElectron Beam DED, also known as Wire Electron Beam Energy Deposition, is a 3D printing process very similar to Laser DED. It is conducted in a vacuum chamber and can produce very clean, high-quality metals. As a wire of metal is fed through one or more nozzles, it is melted by the electron beam. Layers are built individually, with the electron beam forming a tiny molten pool, and the wire is fed into the molten pool by a feeder. Electron beam DED is chosen for processing high-performance metals and reactive metals (such as copper, titanium, cobalt, and nickel alloys).DED machines are actually not limited in size for printing. For example, the 3D printer manufacturer Sciaky has an EB DED machine that can produce parts nearly 6 meters long at a rate of 3 to 9 kilograms of material per hour. Electron beam DED is touted as one of the fastest methods for producing metal parts, although not the most precise, making it an ideal processing technology for building large structures (such as fuselages) or replacement parts (such as turbine blades).
△ Wire Electron Beam Deposition 3D Printing3. Wire Directed Energy Deposition
△ Gefertec Arc Additive Manufacturing (WAAM) PrintingWire Directed Energy Deposition, also known as Wire Arc Additive Manufacturing (WAAM), is a 3D printing process that uses energy in the form of plasma or arc to melt metal in wire form, depositing it layer by layer onto a surface, such as a multi-axis turntable, to form a shape. This method is chosen over similar technologies using lasers or electron beams because it does not require a sealed chamber and can use the same metals as traditional welding (sometimes the same materials).Wire Directed Energy Deposition is considered the most cost-effective option among DED technologies, as it can use existing arc welding robots and power supplies, making the entry barrier relatively low. However, unlike welding, this technology uses complex software to control a series of variables during the process, including thermal management of the robotic arm and tool paths. This technology does not have support structures to remove, and finished parts are usually post-processed as needed to achieve strict tolerances or surface polishing.
△ Gefertec and WAAM3D Wire Arc Additive Manufacturing 3D Printers.4. Cold Spray
△ Cold SprayCold spray is a DED 3D printing technology that uses supersonic spraying of metal powders to bond them together without melting, producing almost no thermal cracks or thermal stress. Since the early 2000s, it has been used as a coating process, but recently, several companies have begun to use cold spray for additive manufacturing, as it can print at speeds 50 to 100 times higher than typical metal 3D processes and does not require inert gases or vacuum chambers.As with all DED processes, cold spray does not produce parts with good surface quality or detail, but the parts can be used directly from the print bed.5. Melted Direct Energy Deposition
△ Melted Direct Energy Deposition: Aluminum Parts Made Using Xerox’s ElemX 3D Liquid Metal PrinterMelted Direct Energy Deposition is a 3D printing process that uses heat to melt metal (usually aluminum) and then deposits it layer by layer on the build plate to form a 3D object. This technology differs from metal extrusion 3D printing in that extrusion uses a metal material containing a small amount of polymer inside to make the metal extrudable. The polymer is then removed during the heat treatment phase, while melted DED uses pure metal. Melted or liquid DED can also be likened to material jetting, but instead of depositing droplets from a series of nozzles, the liquid metal typically flows out of the nozzle.Variants of this technology are in development, and melted metal 3D printers are rare. The advantage of using heat to melt and then deposit metal is the ability to use less energy than other DED processes and potentially use recycled metal directly as raw material instead of wire or highly processed metal powder.7. Sheet Lamination
△ Sheet LaminationSheet lamination is technically a form of 3D printing, very different from the technologies mentioned above. Its function is to stack and laminate very thin sheets of material together to produce 3D objects or stacks, which are then cut into the final shape through mechanical or laser cutting. The material layers can be fused together using various methods, including heating and sound, depending on the material, which ranges from paper and polymers to metals. When parts are laminated and then laser cut or machined into the desired shape, more waste is produced than with other 3D printing technologies.Manufacturers use sheet lamination to produce cost-effective non-functional prototypes at relatively high speeds, useful for battery technology and producing composite materials, as the materials used can be interchanged during the printing process.● Types of 3D Printing Technologies: Laminated Object Manufacturing (LOM), Ultrasonic Consolidation (UC)● Materials: Paper, Polymers, and Sheet Metals● Dimensional Accuracy: ±0.1 mm● Common Applications: Non-functional prototypes, multi-color printing, casting molds.● Advantages: Can be produced quickly, composite printing● Disadvantages: Low precision, high waste, some parts require post-processingLaminated Additive Manufacturing
△ Laminated Additive ManufacturingLamination is a 3D printing technology in which material sheets are layered together and bonded using glue, and then the layered object is cut into the correct shape using a knife (or laser or CNC router). This technology is now less common as the costs of other 3D printing technologies have decreased, and speed and ease of use have increased significantly.△ BCN3D Uses Viscous Lithography Manufacturing (VLM) 3D Printing Process with Resin (Source: BCN3D)Viscous Lithography Manufacturing (VLM):VLM is a proprietary 3D printing process developed by BCN3D that layers thin layers of high-viscosity photosensitive resin onto a transparent transfer film. The mechanical system allows the resin to be laminated from both sides of the film, allowing for the combination of different resins to achieve multi-material parts and easily removable support structures. This technology has not yet been commercialized but could also belong to one of the laminated 3D printing technologies.Composite-Based Additive Manufacturing (CBAM):Startup Impossible Objects has patented this technology, which fuses carbon, glass, or Kevlar mats with thermoplastics to manufacture parts.Selective Lamination Composite Manufacturing (SLCOM):EnvisionTEC, now owned by ETEC, developed this technology in 2016, which uses thermoplastic as the base material and woven fiber composites.Note: There are many types of 3D printing technologies. The above are the seven most common additive manufacturing technologies in 3D printing, but do not cover all the 3D printing technologies on the market.