3D printing is a process that is set to revolutionise the world today. It is a technology that is becoming more and more widespread and is used in many professional sectors. But it is also used by individuals to print various everyday objects. However, although many of us have heard of it, few of us really know how 3D printing works. So let's take a look at how 3D printing works.
What is 3D printing?
3D printing is an additive manufacturing technology that involves depositing and fusing material layer by layer to create a solid 3-dimensional part. 3D printing uses an additive method that consists of shaping an object or part by superimposing layers of material. 3D printing is a technique that relies on highly sophisticated 3D printers that make it possible to manufacture objects and parts in 3D. Different materials, most often plastic or resin, can be used to manufacture objects, the most common being PLA, which is a bioplastic.
How does 3D printing work?
3D printing works through a process of turning digital files into 3D objects, items or products. In order for an object to be created, and before resorting to printing, it is therefore mandatory to start by creating a file that serves as a starting point for a future 3D model. To do this, the usable files will use software that is most often related to the printers used. You should know that there is a multitude of printers and consequently an infinity of software. Furthermore, printers use different technologies depending on the materials and projects.
Thus, we must distinguish between :
Plastic 3D printers:
- The sintering technique: This printing technique called SLS or Selective Laser Sintering which consists of sintering the powder, layer by layer. Once the powder is pre-heated and close to melting, a laser is used to sinter the powder to produce a solid object that conforms to the file.
- Wire deposition technique: This technique, known as FDM or wire deposition, involves using machines with two print heads that deposit the material in the form of filament coils onto a platform layer by layer using a print nozzle.
Resin 3D printers:
- DLS technology involves projecting a continuous sequence of UV images into a bath of liquid resin
- Polyjet technology is similar to inkjet printing, but instead of ink, layers of curable photopolymer liquid are sprayed onto a printing plate.
- LCP/DLP technology involves placing the resin in a tank, where it solidifies against the platform. The object is created gradually as the platform rises.
- SLA technology uses a tank filled with liquid photopolymers that become solid under UV light. The object is printed by moving up and down, allowing the liquid polymers to form the next layer of the object.
- Multicolour 3D printers: work with a roller that sweeps the print tray to deposit the powder layer by layer evenly and at the same time print heads project binders to make the object.
Metal 3D printers:
- Direct Metal Laser Sintering or DMLS will proceed in the same way as for plastic, but the difference lies in the melting point which oscillates around 1,600° as opposed to 200°.
- Selective Laser Melting or SLM is similar to the DMLS technique, except that the melting temperature is even higher so that the powder melts completely. To ensure that the ideal conditions are met, a construction chamber filled with an inert gas is created.
- Binder jetting, on the other hand, uses a binding agent that is deposited on a fine powder in layers. Between each layer, the powder is heated, allowing it to solidify. When the process is complete, the whole assembly is placed in an oven, where it is fired.
What is the difference between professionals and the general public?
Professional 3D printing
Professional 3D printing is based on professional printers that are usually created especially for industry. These are usually huge machines whose function is to produce parts in large quantities, at relatively low production costs and at a high rate. The production of the parts allows quality work with an exceptional level of detail and precision. They are used in sectors as diverse as medicine, automotive, aeronautics, textiles and foodstuffs, to name but a few. In addition to speed, one of the main characteristics of an industrial or professional printer is its ability to produce large objects and prototypes. A professional 3D printer is extremely durable to cope with harsh conditions. The professional printer is also capable of designing products in materials as diverse as plastic, metal, ceramic, etc.
Consumer 3D printing
As you can see, the consumer 3D printer is not intended for the same use as the professional printer. Moreover, this is not what is sought after. The consumer 3D printer market is booming and is aimed at individuals who want to start making products for domestic use while learning about 3D printing. One of the main differences between consumer and professional printers is undoubtedly their price. They are much more affordable, but of course they are also much less powerful and efficient. However, home users will be surprised to discover that some home printers can produce objects with an excellent level of precision and robustness.
