Different 3D Printing Technologies

Hello and thank you for visiting to our 3D printing guide! Today we are going to see about the different types of 3D printing technologies that are used worldwide. So let's start.

Since the first 3D printer was created in the 1980s, there has been a significant advancement in the technologies that are used for 3D printing. These days, there are a plenty of distinct types of 3D printing technologies available, each of which comes with its own set of benefits and drawbacks. In this series of blog, we will talk about some of the most popular technologies for 3D printing, as well as how those technologies function.

There are many variations of the 3D printing process, which include the following:

• Stereolithography (SLA)
• Selective Laser Sintering (SLS)
• Fused Deposition Modeling (FDM)
• Digital Light Process (DLP)
• Multi Jet Fusion (MJF)
• PolyJet
• Direct Metal Laser Sintering (DMLS)
• Electron Beam Melting (EBM

It is safe to say that prototyping is the most common application for 3D printing. Product developers are able to validate their ideas in a way that is both cost-effective and quick thanks to the company's ability to quickly manufacture a single part. To determine which 3D printing technology will be most beneficial for your prototype, you will first need to determine its purpose. Additive manufacturing has the potential to be useful for a wide variety of prototypes, ranging from straightforward physical models to components that are put through functional testing.

Polymer 3D Printing Processes:

Let's discuss common plastic 3D printing processes and when they benefit product developers, engineers, and designers.

Stereolithography (SLA):

In the early 1980s, scientists from France and the United States collaborated to develop a process known as stereolithography (SLA), which was later patented in 1983 by an American named Charles Hull. SLA is a form of additive manufacturing, which is also referred to as 3D printing. This printing method is used in a variety of industries, ranging from manufacturing to biomedicine.

The industrial 3D printing process known as stereolithography, abbreviated as SLA, is used to create concept models, cosmetic prototypes, and complex parts with intricate geometries in as little as a single day. SLA enables users to choose from a large variety of materials, achieve extremely high feature resolutions, and achieve quality surface finishes.

General Principle:

The process of stereolithography, also known as "vat polymerization," is a type of three-dimensional printing. In this method, a liquid, photosensitive resin is poured into a vat (also known as a tank), and ultraviolet light interacts with the resin to selectively polymerize (also known as cure, solidify) it.

The ultraviolet light hardens the resin on a layer-by-layer basis until the finished product is ready. The height of each layer is measured by its thickness, which is also referred to as layer thickness. Layer height in stereolithography is typically somewhere around 50 micrometres, or about the same thickness as a single human hair, but it can be as low as 10 micrometres. In general, the higher the quality will be, but the longer the print times will be, the thinner the layers will be.

The main applications of SLA 3D printing are:

The use of SLA 3D printing is applicable in any setting that requires objects to have smooth surfaces and a high level of precision. This can include anything from architectural models to sonar submersibles and marketing props, but historically, its primary industries have been the jewellery and dental industries.

The most common application of this technique is in the making of jewellery, specifically for casting metal into inexpensive moulds. For instance, jewellers are able to rapidly produce prototypes in order to test different sizes for custom ring orders.

Selective Laser Sintering (SLS):

Carl Deckard, who was studying mechanical engineering at the University of Texas at Austin in the 1980s and ultimately ended up patenting the technology, was the inventor of the SLS technology. Deckard developed the system with the help of his professor, Joe Beaman, and with the aid of a $30,000 grant from the National Science Foundation.

SLS was first developed as a solution to the problem of instant prototyping, and while it has continued to be essential for that purpose, it has also developed into an alternative method for low-volume production to traditional manufacturing methods such as injection moulding.

The industrial 3D printing process known as selective laser sintering, or SLS for short, can produce accurate prototypes and fully functional production parts in as little as one day. There are a number of materials that are based on nylon, as well as a thermoplastic polyurethane (TPU), which can be used to make highly durable final parts that require resistance to heat and chemicals, as well as flexibility and dimensional stability. Because SLS 3D printing does not require the use of support structures, it is a more cost-effective solution for situations in which higher volumes of 3D-printed parts are required. This is because it makes it easier to nest multiple parts into a single build.

General Principle:

SLS is a variation of the 3D printing technology known as powder bed fusion (PBF). In selective laser sintering, or SLS, a high-power laser is used to draw each layer into a bed of powder, which is typically Nylon. The powder particles are fused together into solid structures by the laser, which acts as a sinter. When one layer is finished, the build plate moves down a little bit, and a machine called a powder recoater spreads new powder over the top of the layer that was just finished. This technology has a high degree of accuracy, and the layer thicknesses that it produces typically range from 50 to 200 microns.

When the prints are finished, the person operating the machine has to take them out and de-powder them. Another one of the benefits of using SLS is that the majority of the unused powder can be recycled by simply mixing it in with new powder. However, printing as many components at once as the chamber will allow is the most effective way to use the printer.

The main applications of SLS 3D printing are:

Printing in three dimensions using SLS has applications in a variety of different fields. Prototyping, as well as the production of brackets and enclosures, are two areas in which automotive and aerospace companies make extensive use of it.

In a demonstration of a manufacturing technique known as "ready-to-use," Porsche Classic is currently employing SLS to produce spare plastic parts for some of its most collectible classic vehicles.

In order to construct a high-fidelity audio speaker cabinet in a single piece, Node-Audio made use of the complex geometry capabilities offered by SLS 3D printing.

PolyJet:

The industrial 3D printing process known as PolyJet can construct multi-material prototypes with flexible features and complex parts with intricate geometries in as little as one day. There is a wide range of hardnesses (durometers) that can be purchased, and these work very well for components that have elastomeric properties, such as housings, gaskets, and seals.

General Principle:

The first step in the PolyJet process involves spraying thin layers with small droplets of liquid photopolymers, which are then instantly cured by UV light. Voxels, also known as three-dimensional pixels, are strategically placed during the building process. This placement makes it possible to combine flexible and rigid photopolymers, which are collectively referred to as digital materials. The vertical thickness of each voxel is equivalent to the layer thickness of 30 microns. Accurate 3D-printed parts can be created when thin layers of digital materials are deposited onto a build platform in a step-by-step process.

During the building process, a full coating of support material is applied to each and every PolyJet part. This material is eventually removed by hand using a pressurised water stream and a chemical solution bath. After the manufacturing process, there is no need for any post-curing to be done.

The main applications of PolyJet 3D printing are:

Applications such as concept modelling, rapid prototyping, injection modelling, and functional prototyping are all utilised within the consumer goods industry to assist businesses in accelerating their product design cycle. Even though these can also be printed on FDM printers, the technology provided by Stratasys PolyJet makes it possible for engineers and designers to create more realistic models with a variety of materials, surfacing, finishes, and details. Even the transition from design to prototyping can be accomplished in a matter of hours, rather than days.

Medical device, hospital, and pharmaceutical companies use PolyJet technology to prepare and assist in surgery. Using additional software, one company prints full-size skull MRI scans. Before performing life-changing surgery on children, they carefully plan their operations using the print. Bio-compatible materials approved for 30 days of tissue contact can also be used to prototype and test medical devices.

Multi Jet Fusion (MJF):

The Multi Jet Fusion (MJF) technology is one of the more recent technologies for additive manufacturing (AM) that is currently on the market, and it possesses a great deal of potential. In 2016, Hewlett-Packard (HP) developed a 3D printing technology called MJF. It is a type of the 3D printing technology known as Binder Jetting, and HP asserts that it is quicker, less expensive, and produces more functional parts than its competitors' technologies.

The industrial 3D printing process known as Multi Jet Fusion can produce fully functional prototypes made of nylon in as little as one day. These prototypes can also be used in the final production of parts. When compared to processes such as selective laser sintering, the finished parts have superior surface finishes, higher feature resolution, and more consistent mechanical properties.

General Principle:

A powder recoater spreads a thin layer of powder on the build plate before the printer's ink heads print the first layer. By selectively jetting a fusing agent (a glue) onto the powder, they draw the parts' layers. To improve resolution, a detailing agent is jetted around objects. Heat solidifies the fusing and detailing agents after the print heads deposit them. After that, the build plate lowers and the powder recoater adds another thin layer of powder. Layers are added until finished.

The main applications of Multi Jet 3D printing are:

Engine housings, bellows, baffles, and jigs and fixtures use MJF 3D printed parts for strength and moderate temperature resistance. Examples are below. A local MJF print facility helped Rhode Island prosthetic innovator Michael Nunnery create a fully functional leg socket for a patient. Nunnery said, “His old socket was very loose and heavy, and he is happy with the light weight of the material.” The patient liked the printed prosthetic.

Fused Deposition Modeling (FDM):

Stratasys founder Scott Crump patented FDM 3D printing in 1989. Crump tried melting semisolid plastics in layers with a glue gun to make prototypes faster.

A common type of desktop 3D printing technology for producing plastic components is known as fused deposition modelling, or FDM. Extruding a plastic filament onto the build platform one layer at a time is how an FDM printer accomplishes its function. Producing physical models using this method is quick and efficient, saving money in the process. Functional testing can be done with FDM in some circumstances; however, the technology is restricted due to the fact that the parts it produces have surface finishes that are relatively rough and lack the necessary strength.

General Principle:

Fused deposition modelling (FDM) 3D printing is a "material extrusion" technique. Thermoplastic filament is fed from a spool into an extruder, which melts the plastic and pushes the liquid out of a small nozzle at high pressure. Standard nozzles have a diameter of 0.4 mm, and filaments come in diameters of either 1.75 mm or 2.85 mm.

The print head, comprised of the extruder and the nozzle, travels in a linear fashion along the build plate to sequentially draw each layer. The file, typically in GCODE format, contains instructions for the process and, in essence, a sliced version of the 3D model.

One "slice" represents one "layer." Printing times will increase proportionally with object height because more slices will need to be made. The typical layer thickness of a 3D printer is 0.1 mm. Cooling fans on the print head and/or inside the build chamber help the plastic harden as it solidifies as the print head deposits the filament, melting onto the previous layer.

The main applications of FDM 3D printing are:

Fused deposition modelling (FDM) 3D printing is now being used for a wide variety of applications beyond industrial prototyping, such as mass production and the design of intricate mechanical components. It's especially helpful in the automotive and aerospace industries, where a lot of jigs and fixtures are made.

Fused deposition modelling (FDM) printing is widely used by the automotive industry for everything from prototypes to replacement parts for vintage vehicles. The German company BigRep is a notable example; they used their FFF 3D printers to create a fully functional motorcycle (the NERA).

Metal 3D Printing Processes:

Direct Metal Laser Sintering (DMLS): 

Direct metal laser sintering (DMLS) is an additive manufacturing process that employs a computer-controlled, high-power laser beam to melt and fuse layers of metallic powder.

Powder Bed Fusion includes DMLS, the most popular additive method for creating metal prototypes. Metals such as aluminium, stainless steel, titanium, cobalt chrome, and Inconel can be processed in a manner analogous to selective laser sintering of plastic resin. It has high precision, a high level of detail, and superb mechanical properties.

Industrial metal 3D printing with direct metal laser sintering (DMLS) can create fully functional metal prototypes and production parts in as little as 7 days. Metals with different properties are used to make parts that serve different purposes.

General Principle:

DMLS models, slices, and prints layer-by-layer like most 3D printing technologies. After a 3D model is created and sliced with the right software, the printer receives the code to make the part and the physical process begins.

Fill the DMLS printer hopper with metal powder. Printer heaters heat powder close to alloy sintering temperature. Inert gas protects the heated powder and part as the printer builds.

The build starts with a thin layer of metal powder on the platform. The laser sinters the powder in this layer. Sintering and dispensing continue until part completion.

After cooling, the printer removes loose metal powder. Support removal and post-processing conclude the process. DMLS parts can be further processed like conventional metal parts. Machine, heat, or finish. SLM uses these steps with the laser turned up to "melt".

That's it guy for the day. Today we have seen the major different 3D printing technologies, stay tuned  for more information till then good bye!!!