3D printing technology has captured the attention of designers and made headlines all over the world with enticing stories about the sophisticated projects that have been accomplished.
Inasmuch as the technique may look relatively new, the truth of the matter is that it has been in existence for quite some time since way back in the 1980s when it first emerged. The technology has increasingly improved with 3D metal printing coming to the scene and going from strength to strength. It has gradually found its way in various industrial applications in the production of a wide range of products.
So, can 3D printers print metal? The answer is yes provided that the 3D printer in question is designed specifically for printing metals in three-dimensional.
One of the main reasons as to why metal 3D printing is increasingly becoming popular is perhaps its ability to serially 3D print parts for mass production. As a matter of fact, some metallic parts that have so far been created through metal 3D printing have already exhibited superior quality compared to those manufactured using the traditional methods.
This comes as good news to those embracing this new technology thus paving the way for innovative ideas resulting from 3D printing. This article will take you on a step-by-step process of 3D metal printing, how accurate the process is, the metals that can be used and how much 3D metal printer can cost you. Learn more about this amazing technology in the subsequent paragraphs.
The Process of 3D Metal Printing
Metal 3D printing is actually an additive technology as opposed to the subtractive processes. This means materials are gradually added to come up with a finished product rather than being taken away just like in milling or turning. Here is a comprehensive explanation of what the process entails:
To begin with, your 3D metal printer will need a computer-aided design or CAD design for you to initiate the process. The CAD design involves creating detailed images from every angle of the desired design. You will need to use the CAD software to help you in completing the design and then convert it into a .stl format. The .stl format is used to enable 3D metal printers to interpret the laid-down instructions.
Don’t forget that the metal 3D printing is a process that takes a multi-layered approach in the same way as the rest of 3D printing forms. In other words, the process requires the designs to be sliced finely right at the horizontal plane before the entire process takes effect.
As usual, every 3D printer performs its task by taking instructions from the computer whereby the software instructs the laser what it is supposed to do. For instance, the instructions may direct the laser to trace out a particular shape across the powder/printable materials in order to create the desired shape. Consequently, the laser on the printer will pulse and then heat up the printing materials (in this case, the powder) to create a solid form. In real sense, this is how 3D printing takes place in metal designs.
After the initial base has been successfully laid out the printing process starts all over again. Each layer is laid out across the bed and you will realize that it is not more than 0.1mm in thickness. The process is gradual and will eventually lead to printing out 3D metal objects where the intense heat from the laser forms a solid shape.
However, the process may either be the Selective Laser Melting or Direct Metal Laser Sintering. Each process is determined by the heat used in the process or the melting of the powder. The powder melting can either be complete or just heated to the extent of fusing together. But don’t confuse these processes with the methods used in 3D printing metal. These methods include metal binder jetting, powder bed fusion and direct energy deposition.
Top Three Methods for Metal 3D Printing
Below you will find a quick overview of the top 3 most popular ways to 3D print metals:
1. Metal Binder Jetting
When using Metal Binder Jetting as your method, your 3D printing will start out just like other printing processes. First of all, you will need a very nice 3D design and an awesome slicer to tell your printer where the print head needs to deposit materials. Unlike most of the other 3D printing process where plastic is extruded, here the metal powder is rolled or deposited in thin layers and then bound with the help of a glue-like binding material that is ejected out from the print head and spread evenly on each layer.
These alternating layers of the binder and powder fuse together while gradually building up the desired 3D object. The entire process is repeated in order to complete all the layers starting from the bottom coming to the top. The whole process is likely to take several hours to be fully completed.
Keep in mind that upon the completion of the build-up process, the model comes out fragile because most of it is still porous and filled with air. To harden it, you will need to place it in a curing oven at a temperature of about 350 Fahrenheit for a whole day. The reason for using this temperature is to evaporate the moisture and harden the binder in-between the layers of the metal powder. Once the object is fully hardened and cooled, the next process is to fill it with materials such as bronze filler to give it some strength.
The advantage of using the binder jetting method is that you can do color printing as well as working on ceramic and polymer materials. Also, the whole process is faster than the rest of other additive manufacturing processes.
2. Powder Bed Fusion
Powder bed fusion is almost similar to the metal binder jetting but the difference comes about where instead of using a binder, an electron beam or a high-temperature laser is used. During the process, the laser raises the temperature of the metal powder in sections where the designs are being created by fusing the powder while building a solid layer.
The whole process continues until the model is completed. Apparently, the powder bed fusion process can be carried out using any of the common techniques used in 3D printing like the Selective laser melting (SLM), Selective laser sintering (SLS), Electron beam melting (EBM) and Direct metal laser sintering (DMLS)
3. Directed Energy Deposition
This method uses two types of different materials. These are metal powder and metal wire. During the process, a nozzle moves in different directions (let’s say 4-5 axis) to extrude metal wire material or metal powder layer by layer. The moment the extruded materials get deposited, they are melted immediately with an electron beam or laser.
The whole process continues and objects are created layer by layer throughout. Despite the fact that the process is popular in the maintenance of existing metal materials, it can as well be used to build up objects right from scratch when 3D printing.
Is 3D Metal Printing More Accurate than Photo etching?
The answer to the question of whether 3D metal printing is more accurate than the etching depends on the understanding of how each method works. Both methods are awesome especially when it comes to creating impressive and detailed objects.
In as much as the two techniques have striking similarities, there are as well great differences between them. One major difference emerges in the manner with which the items are built. With 3D metal printing, the entire process is additive but the photo etching is a subtractive method where materials are cut away from the main body to reveal a shape or pattern using a laser tube.
However, photo etching, especially by laser cutting, is extremely accurate thus a better choice of technology to create intricate, precise cuts in a timeless manner. On the other hand, the 3D, as mentioned earlier, creates objects by using the printer to add layer by layer in order to come up with a final product. Therefore, it is not right to say that 3D metal printing is more accurate than photo etching given that the 3D printing is still in its infancy stages.
What Metals Can You 3D Print?
Three-dimensional metal printing requires special types of metal materials and here is a complete list of metals that are often used in this process:
- Sterling silver
You need to be fully aware that metal three-dimensional printing needs some special type of CAD designs to guide your 3D printer across the entire process.
How Much Does a 3D Metal Printer Cost?
Quite a number of professionals and industrials are increasingly turning to metal 3D printing to build up metal three dimensional printed customized parts or prototypes on demand. But most of the 3D metal printers are relatively costly with their prices ranging from $80,000 all the way to $100,000.
These machines are suitable for many industrial applications such as automobile, aerospace, engineering, health and so on. In short, 3D metal printers are expensive not only when acquiring them but when it comes to their high maintenance including high energy fees.
By now you have first-hand information regarding 3D metal printing as the latest technology for various industrial applications. Even though the method is still in its infancy, the best part of it is that it is making a number of tasks and projects possible unlike how it was in the past.