You might be surprised to learn that 3D printing with metal is actually possible. Whilst more common for businesses, it has become a fast growing and widely used area of technology within industrial manufacturers.
It is so advanced that it can replicate ‘real’ looking machine parts that are usually used in prototypes or finished products such as in mechanical engineering, some tools, aerospace, etc.
Whilst it might seem like it is obvious what metal 3D printing is, it is actually an umbrella term that covers different forms of technology which create metal by using layers. This can be done by melting, welding or sintering.
Metal 3D printing is greatly invested in due to its capabilities. As such an exciting technology, let us take a look at what 3D printing is, the limits of using metal, and the different ways it can be done.
The Main Technologies
When it comes to the main technologies, there are three that are really useful for printing 3D metal. These are SLM (Selective Laser Melting), DMLS (Direct Metal Laser Sintering), EBM (Electron Beam Melting) and SLS (Selective Laser Sintering).
We shall take a look at these in more detail below, and then see what the advantages and what limitations there are with printing metal.
Selective laser melting (also known as direct metal laser printing) does exactly what it says – melts the metal. Because 3D printing takes place in an environment of static gas, the conditions stay nearly the same as if it was being created by casting. That method usually involves some form of mold.
The metals used for this process are normally aluminum and titanium which are referred to as ‘pure’ materials.
How SLM Is Used
When an object is made with SLM, it has durable properties that make it great for the use of mechanical parts used by the likes of automotive, aerospace and medical industries.
This is because SLM is said to be one of the most exciting 3D printing technologies available currently due to it being able to produce metal that has such similar qualities compared to a traditional method of manufacturing metal.
So how does it get put together? To put it very simply, the laser melts powdered metal together in layers until the final model is complete.
Whilst SLM is an appealing form of metal 3D printing, DMLS, or direct metal laser sintering, is by far the most popular way to print 3D metal.
There are many materials available for DMLS 3D printing such as cobalt chromium, aluminum AISi10Mg, maraging steel, titanium Ti6AI4V and inconel 625.
How DMLS Is Used
Even though the metal powder can reach temperatures of nearly 3000 Fahrenheit, the metal does not melt. It uses a laser to sinter the metal powder which forms an object using layers.
It is extremely practical for creating prototypes, as well as having the capability of manufacturing mechanical parts that have intricate cavities and draft angles. This is especially useful when creating medical devices and tools.
Whilst the two other technologies use a laser, an EBM (also known as electron beam melting) uses an electron beam instead. It is said to work more precisely as well as faster, making it a good option for printing metal.
Even though it has these advantages, it does not make a huge difference to the final outcome of the metal product.
How EBM Is Used
However, even so, the finished product does turn out stronger than other methods, so it is used with cobalt and titanium. Because of this, it is used for aircraft and space missile parts, amongst materials for engines and so on.
Once a widely used method for many materials, now that is not so. These days selective laser sintering is mainly used for sintering plastic such as polyamide and nylon. Because of this, SLS printers only tend to reach around 400 Fahrenheit, if that.
How SLS Is Used
Selective laser sintering is not as popular as the above three methods, but it is very similar to direct metal laser sintering. Both of these methods use a laser to sinter the powdered metal.
Other Technologies To Look At
There are other technologies within metal 3D printing we can take a look at briefly. Whilst not as common, they are very interesting to learn about. These are:
Powder is binded to a specialized liquid which is then subjected to a hot isostatic pressing which makes it solid. Whilst it makes the object stronger, it is also more expensive. It is used within large-scale manufacturing and requires post-processing.
Laser Metal Deposition
Used within aerospace, medical and the automotive industries, different materials can be added to this metal such as steel alloys. The metal is heated and deposited in layers which materializes the object.
Advantages Of Using Metal To 3D Print
The useful thing about 3D metal printing is that you can manufacture a complex shape. This helps if you are creating an intricate mechanical part for something as important as space missiles or a medical device. Other technologies may struggle to do such a thing, so 3D printing with metal has made it possible to do it much faster and easier.
Due to the printer being able to work precisely on very small, tiny details, it also means the object can be extremely light. This is another reason why 3D printing metal is a popular choice within the aerospace industry.
3D printing also does not waste as much material making it more efficient. This keeps the cost down and less material goes unused, which is better for the environment if it has to be thrown away.
Limitations of Using Metal to 3D Print
Whilst 3D printing metal has been revolutionary for many industries, it does not come without its limitations. It is actually a lot more expensive than traditional methods, and this can be a problem if you want to do large scale amounts. Usually that is not an option industries choose when it comes to 3D printing.
Because powdered metal is used, the material is a lot more expensive than traditional regular metal. Powder has to be used because when regular metal is used, production is a lot slower.
There are times when post-processing is needed, which is time consuming and can cause more stuff to be done in the production line. This also means that more money may have to be spent.
Even though 3D metal printing can produce intricate designs, it means you will need to find professionals who can do this using CAD. As a standalone person who may want to print with metal, this might not be a viable option, so printing with metal might turn out to be a lot more complicated.
Also, you can not manufacture large pieces of metal, so it is best to use the printer for mechanical parts.
Whilst many people think of plastic when it comes to 3D printing, you can actually 3D print with metal. It is a difficult thing to do within the home, however, it is widely used within the aerospace, automotive and mechanical industries.
Not only can it work on intricate and complex designs, but it is durable and strong, making it a reliable way to produce small metal objects needed for bigger things.