Era of Metal 3D Printing
“3D Printing is already shaking our age old notion of what can and can’t be made”— Hod Lipson
Introduction
As the name suggests Metal 3D Printing is printing 3-dimensional objects which an upgradation to the old plastic prints. Metal 3D Printing is a laser-based technology that uses powdered metals. A high-powered laser selectively binds together particles on the powder bed while the machine distributes even layers of metallic powder creating an extruded object. Many Metal 3D Printers directly use metal wires instead of powdered metal which are melted tiny bit at a time using an electric arc.
Obviously, the objects are designed precisely using different software before they can be printed. Software’s such as GrabCAD 3D, Autodesk 360, Blender and SolidWorks are used. Materials which are widely printed are steel, titanium, chrome, Inconel and aluminium.
Types
Metal 3D Printing is not a new concept, but the advancement made in the last five years are really amazing. The various types of Metal 3D Printing techniques are :
- Powder Bed Fusion: Most common type of metal 3D printing. These machines use a fine layer of powder and selectively melt a cross section of part into the powdered layers. There are two types pf Powder Bed Fusion techniques-
· Selective Laser Melting (SLM): Most of Powder bed Fusion machines are Selective Laser Melting (SLM) machines. SLM machines use excessive powered lasers to fuse metallic layers into parts. After a print, an operator eliminates the component (or components) from the powder bed, cuts the component away from the construct plate, and post processes the element. It’s the modern-day general for metallic printing — most agencies in steel AM today sell SLM machines.
· Electron Beam Melting (EBM): EBM machines use an electron beam in place of a laser to fabricate components. The electron beam yields a less precise element than SLM, however the process as an entire is faster for larger components. these machines have nearly all the same constraints, fees, and problems as SLM machines, but are used greater closely in aerospace and medical programs than everywhere else. In addition to SLM, EBM machines require a dedicated technician to run.
2. Direct Energy Deposition (DED): It uses of metal feedstock and a laser to fabricate parts. Unlike powder bed fusion, the stock (which may be powder or wire) and the laser each sit on a single print head that dispenses and fuses material simultaneously. The resultant elements are very just like Powder bed Fusion, with a few key differences and possibilities. These are also of two types-
· Powder DED: It is very similar to SLM using laser and metal powder to fabricate the metal parts. Instead of spreading powder on a bed and melting it with a laser, DED machines precisely blow powder out of a print head onto a part, using an on-head laser to fuse it to the part in construction.
· Wire DED: It also uses laser to melt feedstock, but in this case the feedstock is a metal wire instead of powder. Wire DED parts are designed comparatively large and less precise than Powder DED.
3. Binder Jetting: The machine evenly distributes metal powder over the print bed, forming an unbounded layer. Then a jetting head distributes the binding polymer in the same shape of the part cross section, adhering the powder. This process repeats until a finished part is printed. Parts printed from this machine requires sintering to become fully metallic.
4. Bound Powder Extrusion (BPE): This is a newcomer in Metal 3D printing space. Unlike other methods BPE machines do not use loose powder metal. Rather the powder is bounded together in waxy polymers. As a result, a material which is much easier and safer to use than loose powder is used. Parts printed from this machine also requires sintering.
Advantages
Metal Printing have many advantages over conventional methods of manufacturing. But, among those the most important ones are:
· Increases rate of production: Traditional methods require different tools and equipment which themselves might be difficult to manufacture. 3D printing not only increases rate of production but also decreases the complexity of manufacturing
· Reduces cost: With regards to metal additive manufacturing, 3D printing technology is an affordable and cost-efficient alternative to produce parts and tools compared to the traditional machining.
· 3D Printers can make parts no other machine can: Metal 3D printing is capable of fabricating parts that cannot be made with any other platform. Any complex and custom parts can be manufactured where conventional method fail.
Applications
In the past five years manufacturing industry has seen dramatic advancements in metallic materials, low-cost printing and new technologies. Some applications are-
· Aerospace Industry: To manufacture parts which are complex to manufacture with traditional methods
· Automotive Industry: To manufacture parts such as pistons and brake calipers for high strength and performance properties.
· Medical: To make surgical equipment's, surgical and dental implants with high accuracy and durability.
· Jewellery and Decorative Arts: To print complex and delicate geometric designs out of precious metals.
3D Printing a rocket
There are many applications of Metal Printing as stated above. But, apart from this, metal printing is used in an interesting and fascinating way, that is to 3D print a rocket, yes an entire rocket that will actually go in outer space. The advantage of 3D Printing a rocket is that it is just a single part, consumes less amount of time to be manufactured and most importantly cheaper, around 10 times cheaper. This could potentially be the next big evolution in the aerospace industry.
References
Authors-
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