Technology today is advancing extremely fast and there are almost no impossible things. This includes 3D printing and prototyping. So many things have been done in the production of additives for metal parts that this is a outstanding example of what a revolution is taking place in the creation of new technologies.
One leading technology is the so-called Selective Laser Melting. But the question is what is it and how does it work? In this article we will talk about this.
What is this technology?
Selective Laser Melting (SLM) is a type of production of metal additives or 3D printing. You will often find this technology under the name DMLS, which means “direct metal laser sintering”.
Although the two technologies are similar, there is a small difference between them. If the task of the SLM is to melt metals, then that of the DMLS melts or agglomerates metals. For this purpose, a laser is used, which acts as a direct source of energy. Thus the metal turns into a metal powder.
Selective Laser Melting is one of the greatest 3D printing technologies available today. It is used not only for rapid prototyping, but also for mass production. The range of available metal alloys is quite wide. And the end result has properties equal to those produced using traditional production processes.
Here it is important to share the difference between SLM and another similar process, namely Selective Laser Sintering (SLS). In short, we can say that the two processes are very similar to the main difference that they use different materials.
Selective laser sintering is used in processes in which the materials are plastics, glass and ceramics. In addition, the sintering process does not completely melt the powder, but heats it to the point where it can be fused at the molecular level. This allows control over the process.
On the other hand, in Selective Laser Melting the process is similar, but applied to metal alloys. Also here the laser is used to achieve complete melting. This means that the powder is melted into a homogeneous part. This leads to a product that is composed of one type of material, as there is only one melting point.
How does Selective Laser Melting work?
As we have already shared, SLM is very similar to the DMLS process, as both are involved in fusion. In SLM, the laser melts the powder layer by layer until the model is complete. At the molecular level, the powder is melted to obtain a homogeneous part.
This process uses mainly pure materials, such as titanium, stainless steel, cobalt and aluminum, and much less often alloys can be used.
Quite often, due to the weight of the material used, Selective Laser Melting technology requires the addition of support structures, although there is a powder bed that supports the work during printing.
As with other 3D printing technologies, SLM also uses a 3D CAD model, based on which the desired real object is created. This process is possible thanks to the high-energy laser beam, which takes care to melt the metal dust so that the object can be created.
Application
SLM technology is extremely suitable for the fabrication of complex geometries and structures that have thin walls and hidden cavities and channels, as well as those that are small in size. This technology is widely used in medicine, helping to create a stem for the hip joint, for example, as well as for orthopedic implants and much more.
Selective Laser Melting is also used in the aerospace industry. Thanks to it, components can be produced that would be difficult to produce in traditional production. The huge advantage is that thanks to Selective Laser Melting, small parts can be made, such as spare parts for old machines.
In short, the technology is used to produce direct parts for industries such as aerospace, dental, medical, manufacturing and many more. These parts can be small to medium in size, including very complex parts, as required in the tool industry.
Although the technology is expensive, it saves a lot of time, as it can be used for rapid prototyping. This, in turn, saves valuable time for developing new products as well as subsequent production time.
In China, for example, they used a similar technology that was used to build structural titanium parts for aircraft. Research shows that using this process can reduce materials and waste in the aerospace industry.
And even more interesting is that in 2018 it was approved in the first ever implanted spine, which was made of titanium, using the Selective Laser Melting technology.
Industries in which SLM finds application are:
- the aerospace industry – for equipment, such as air ducts, fixtures and supports, which have specific aeronautical instruments.
- medicine – for the manufacture of complex medical products of high value, including various types of implants.
- rapid prototyping – helps to create design prototypes that are affordable and functional and enable the creation of the perfect product.
- tool processing – helps the rapid production of tools, as well as the optimization of existing ones so as to improve their functionality and much more.
SLM is an extremely interesting technology that has huge potential for wide application. Today, interest in it is growing very fast, which leads to the development of technology, and the process itself is becoming more accessible to consumers.
Do you need an expert?
This technology itself is complex, so not everyone can do it. It requires you to have specialized design and manufacturing skills and knowledge to handle the making of the necessary part.
That is why it is necessary to turn to experts who will surely know how to use Selective Laser Melting technology.
Feature of 3D printers used in this technology.
When choosing 3D printers to use with this technology, you should first of all pay attention to whether they are designed for it.
The features that are important for such a printer are:
- speed – it is extremely important for any 3D printer, even for those who are for SLM.
- size – what will be the size of the selected printer, it matters how big the models will be able to print.
- accuracy – accuracy is related to the resolution of the 3D printer so that the most accurate dimensions can be printed.
- Durability – It is important that the selected printer is resistant to the high loads that are possible with this type of printing.
- materials – this is a key feature when choosing a 3D printer. For the purposes of Selective Laser Melting technology, the device must be designed to work with metal.
The most important thing you need to know about Selective Laser Melting 3D printers is that they need to be filled with metal powder to get started. In addition, the whole process must be performed in a controlled environment, which means that you must have a closed chamber that can withstand a certain temperature in Celsius.
But to be sure of the right choice and whether Selective Laser Melting is suitable for your purposes, we advise you to always consult a specialist. They are able to explain the whole process to get the product you need, as well as guide you in what the 3D printer should be that best suits your needs.
