What really goes on inside a 3D printer? How can a three dimensional real life object be formed based on the virtual concept contained within a digital file? Is the additive process really as advanced as we think it is? The answers to all those questions need not be complicated. You certainly do not have to be an employee at Microsoft or Google to understand how 3D printers work. You just need to have a little bit of common sense and a keen interest in future technologies. Future technologies are exactly what we will be discussing today. We are not years away from the reaping the rewards of such technologies. As a matter of fact, thanks to the concept of 3D printing, future technologies will help us pave the path to the construction of a multi-billion dollar 3D printing industry in the near future.
3D Printer Processes and Technologies
Although a lot of people believe that 3D printers are all based on the same technology, it would be quite silly for us to assume that a single technology is responsible for all the 3D printing activities that are taking place around the world. There are a number of ways in which you can 3D print an object. What is remarkable is that all those ways involve additive processes. The difference between the processes or the technologies lies in the way the layers are constructed to create the final object. In certain methods, melting or softening material is used to produce the layers. The two names that you should remember if you are genuinely interested in learning about the technologies upon which 3D printing is based are selective laser sintering (commonly referred to as SLS) and fused deposition modelling (commonly referred to as FDM). These are the two most common technologies used in this form of printing. Another common technology that is used is called stereolithography (also referred to as SLA). Understanding these technologies is key to understanding how 3D printers function.
The 7 Categories of Additive Manufacturing Processes
As the 3D printing industry expands, it is important for people to get a hold of all the different technologies that are being used. Hence, for the convenience of learning, organizing information and spreading information, the American Society for Testing and Materials (abbreviated to ASTM) has come up with a group called the ASTM 42- Additive Manufacturing, which is responsible for developing a set of standards that divide the Additive Manufacturing process into 7 categories that are based on the Standard Terminology for Additive Manufacturing Technologies. In simple terms, there are 7 different types of additive manufacturing processes or technologies that you should be familiar with. These seven processes are listed below along with brief descriptions:
1) Vat Photopolymerization
3D printers that are based on this technology are retrofitted with a container that is filled up with photopolymer resin. This photopolymer resin undergoes a process in which it is hardened via exposure to UV light rays. The most commonly used technology in Vat Photopolymerisation is stereolithography that has been previously mentioned in this article. This entire technique was originally invented in the year 1986, by Charles Hull. He was the founder of the company, 3D Systems during that period in time. Even though 3D printing is very new, the technologies that it is based upon are not necessarily 21st century inventions.
2) Material Jetting
A small diameter nozzle, which resembles the main component of the common inkjet printer, is used to apply the material in droplets. The droplets are applied layer by layer to a build platform. The droplets are then hardened by UV light rays so that the solid 3D object is formed.
3) Binder Jetting
Binder jetting uses two materials. The first one is a powder base material and the second one is a liquid binder. The powder is spread in equal layers inside the build chamber. As for the liquid binder, it is applied through a jet nozzle. This technology was first introduced by MIT in the year 1993.
4) Material Extrusion
Various technologies are used in this 3D printing process, but the one that is most commonly relied upon is the fused deposition modelling (FDM). Scott Crump is the inventor of the FDM, and he came up with his creation in the late 80s.
5) Power Bed Fusion
Selective laser sintering or SNL is most commonly used to carry out the process of power bed fusion. A high power laser is used to fuse small particles of metal, plastic glass or ceramic into a mass that is moulded into a specific three dimensional shape.
6) Sheet Lamination
Materials in the form of sheets are used in this process. The sheets are bound together by external forces. Metal, paper or a specific form of polymer can be used as the constituent element for the sheets.
7) Directed Energy Deposition
You will find this process being used in high-tech metal industries as well as in rapid manufacturing applications. A multi axis robotic arm is connected to the 3D printing apparatus. Metal powder is deposited by a nozzle and is then melted by an energy source to form the desired 3D solid object.