3D printing is the newest and most technological production system in the industry.
We are talking about innovation and therefore Industry 4.0, digital technology capable of overturning traditional production paradigms.
Additive manufacturing? What is it?
It is a real revolution, production no longer takes place by removing material from solid …. it starts with a virtual 3D model and then, thanks to the use of special 3D printers, it is “printed” layer by layer, as happens in ink printers we have at home or in the office.
The additive process in the production phase is characterized by a printing cycle in which these innovative machines allow the creation of extremely complex geometries.
But what needs to be kept in mind is that it’s not just FFF technology, there are multiple printing technologies!
The most used printing technologies in the industry
The first thing to understand is that using the term 3D printing is very generic, because it identifies a group of additive manufacturing processes of an artifact.
The ISO / ASTM 52900 standard, created in 2015, seeks to classify the different types of 3D printers in the most specific way.
In total, seven different categories of additive manufacturing processes have been identified and established.
BUT … in the industrial sector, the most used technologies are three:
FDM stands for Fused Deposition Modeling
The most common method used in the additive world is that of FDM printing which is based on the use of thermoplastic materials, melted by means of a heated extruder.
A three-axis system moves the extruder along the XY axes until the definition of the first print layer on the print platform is complete. Once the first level is completed, the extruder moves along the Z axis and resumes extruding material to define the new level.
The repetition of the printing cycle and the overlapping of the layers composes the final geometry.
The SLA (StereoLithography Apparatus) process is based on the combination of a liquid resin that is photosensitive to a beam of ultraviolet light to solidify the resin.
This type of printer uses mirrors called galvanometers, positioned on the X and Y axes, to point a laser beam through a resin tank.
A section of UV liquid resin is selected which solidifying layer upon layer forms a cross section of the object within the printing area.
This method has been used for some years above all in the dental and jewelry sector.
Engineers and manufacturers from different sectors rely on 3D printing through selective laser sintering (SLS) because it allows the creation of robust and functional parts, moreover compared to traditional FDM or SLA is the possibility of 3D printing without the need to create supports.
The SLS process uses a laser that melts a powder, which in turn solidifies on the previous layer. In fact, the unsintered powder inside the printing chamber acts as a support for the sintered part.
It is therefore possible to create geometrically complex and reciprocally moving parts in a single printing process. The parts made are free of delamination and have the advantage of being isotropic, that is, they have the same mechanical response when stressed along different directions.