Metal 3D printing
Currently, 3d metal printing is considered as one of the most promising technologies, which in the near future may supplant modern prototyping methods.
Researchers are working hard to ensure that in the near future printers using metal, appeared on construction platforms, in the metallurgical and food industries.
It seems that the “Terminator” creators predicted the future
Just imagine how our world will change for the better, if each of us can start the production of metal structures and structures just at home.
Talking about the prospects of metal printing can be infinite, but for a start it is better to understand in more detail what modern 3D metal printers are.
More recently, founding was considered as the only inexpensive and economically advantageous method of manufacturing three-dimensional metal structures.
With the advent of FDM printers, its high position was somewhat shaken, but at the beginning of the two thousandth, few people believed that three-dimensional printing technology was evolving to such an extent that the issue of complex reformatting of the metallurgical industry would be on the agenda.
The principle of layer-by-layer growing of a volumetric object was initially used only when creating machines that work with plastic and clay.
A lot of time passed before a 3d metal printer appeared, which could provide a worthy competition to traditional methods of metal production.
Metal 3D printing technologies
At the moment there are only a few technologies that are used for metal printing: laser 3d printers and inkjet. Both of them imply a neat and gradual layering of the “ink” layer by layer to build a given shape. However, the engineers found several ways at once to grow a solid object on a building platform.
Selective laser sintering
The SLS technology, also known as Direct metal laser sintering, allows you to create metal objects from a fusible powder — metal clay. For the first time this material was shown in 1990 in Japan. Then it was used for modeling primitive forms. In industry, it began to be used only ten years after opening.
Metal clay is made from a mixture of metal shavings, an organic binder and water. When fired, the binder and water burn out, which turns the metal powder into a solid object.
SLS printers use a laser for machining metal sheets. The powder is applied to the surface of the platform in an even layer, after which it is smoothed with a special roller. Then, the laser radiation corrects the layer of metal clay as it is programmed in the template.
The process is repeated time after time, until the figure becomes the right size. Printing takes place in a special chamber with an oxygen-free environment in which high temperature is constantly maintained.
Engineers claim that products made using selective laser sintering are superior to metal blanks created by the traditional method in parameters such as porosity and strength.
By the way, industrial laser 3D printer is already used by such giant as General Electric Aviation.
Electron beam melting
EBM technology is essentially the same as metal printing from SLS / DMLS. The only difference in the electron-beam melting is that instead of the laser beam, the metal plate is melted with the aid of directional electric pulses.
The use of high-power electron beams operating in a vacuum provides higher detail for printed objects. This is because the adjustment of the electron beam is carried out not by the movement of the print head, but by manipulating magnetic fields, that is, at a much more accurate level.
The use of electromagnetic components instead of laser lenses makes EBM printers more cost-effective compared to laser equipment. In addition, they provide better performance.
It should be said that the above-mentioned technologies are far from their limit and can become even better. Despite the fact that designers use high-precision equipment that is superior to traditional methods of metal processing, when designing layouts for printed products, shrinkage from 8% to 30% has to be taken into account. This is due to the physical properties of the “ink”.
In addition, we should not forget that EBM and SLS / DMLS machines are equipped with germanium and diamond lenses, complex electromagnetic devices and silver-plated or gold-plated mirrors, because of which the cost of equipment makes its purchase profitable only for large industrial centers.
Fused deposition modeling
FDM or fused deposition modeling technology is used primarily in printers working with plastic, wax and resin.
The principle of operation of devices using this technology is quite simple: the molten material is extruded through an extruder onto a cooled building platform, where it freezes, forming layer by layer the desired object. 3d printing from metal by the method of fusing is considered as the easiest of the methods of printing available by metal. Of course, it is not without flaws.
Despite the abundance of “ink” available in the form of metal clays (copper, steel, iron, bronze, silver and gold), the existing FDM equipment is not capable of printing metal objects with high definition and detail.
Among the devices operating on a similar principle, we can distinguish The Mini Metal Maker.
It is possible that the 3d printer metal in the foreseeable future will appear in the house of everyone. This is evidenced by the rapid development of the industry: today industrial whales such as General Electric, Mitsubishi, Boeing, General Motors and Lockheed Martin use EBM and SLS / DMLS printers in their production.
The companies claim that 3D printing helps them to save significant sums of money and significantly expand the possibilities of conveyor production of components.
It is unlikely that 3D Systems and Arcam, which owns primacy in this area, will be able to remain monopolists in the market for a long time and dictate their prices to consumers.
Despite all of the above and the fact that most of the patents expired in 2015, which, according to the basic laws of market competition, made home factories for the production of metal structures available for household use, they did not receive such wide distribution.