Additive Manufacturing (AM) is an emerging technology which offers an alternative to conventional manufacturing processes. Through the successive deposition of layers of material it is possible for objects to be built directly from a CAD model (computer-aided-design) of the piece, and this method is proving to have vast potential in strategic sectors such as aerospace, automotive and energy.
This manufacturing method makes it possible, among other things, for all geometric shapes, including the most complex ones, to be reproduced without the need for any tools or equipment, likewise, it offers immediate results and it can be used to personalise any item (customisation). Nowadays this technology is able to produce 100% functional pieces which offer high added value, making it a major competitor to traditional machining and forming processes.
AM is currently one of the industry 4.0 technologies which are making it possible for smart factories to be launched; these factories are able to adapt better to the needs and flexibility of the production processes.
AM processes in the industry
There are a wide range of processes within the additive manufacturing industry which make it possible for pieces to be manufactured from different materials, offering different qualities and usages. The international ASTM Committee F42 on Additive Manufacturing Technologies standardised the processes in seven categories:
- Material Extrusion: an additive manufacturing process in which material is selectively dispensed through a nozzle or orifice.
- Material Jetting: an additive manufacturing process in which droplets of build material are selectively deposited.
- Binder Jetting: an additive manufacturing process in which a liquid acts as a bonding agent after being selectively deposited between the powder material to be bonded.
- Sheet Lamination: an additive manufacturing process in which the sheets of material are bonded to form the final piece.
- Photopolymerization: an additive manufacturing process in which a liquid photopolymer is selectively cured by light-activated polymerization.
- Powder bed fusion: an additive manufacturing process in which energy selectively fusions material deposited on a powder bed.
- Directed energy deposition: an additive manufacturing process in which thermal energy, produced by different systems, is used to fuse the materials which is being deposited on a surface.
A fundamental aspect when developing these technologies is the heat input source which is used to deposit each layer of material, and out of these laser is amongst the most commonly used. This is why out of all of the additive manufacturing technologies, it is laser additive manufacturing which has the greatest potential for the manufacturing of metallic components.
Sectors in which it is being implemented
AM technology is present in a wide range of industrial sectors, including biomedical, aeronautic, automotive, energy, defence and textiles.
The commitment to reducing the weight of parts, while still managing to maintain the same mechanical resistance in both the aeronautic and the automotive sector has led to an increased use of additive manufacturing in the creation of prototypes, the validation of new models, and the production of components with variable thicknesses and functional pieces, amongst others.
In the energy and defence sector, this technology is now being used due to the potential it offers for manufacturing small series of complex geometric pieces quickly and at a competitive price.
Another sector in which additive manufacturing is being implemented is in the textile and furniture sector as this technology can be used to design different shapes without limitations. These uses can be extended to the consumption goods sector in general.
It is clear that AM is already becoming a real alternative to conventional manufacturing processes. These days huge investments are being made into R+D, looking at ways to make these productive processes more profitable while using a wider range of materials.
 ASTM Standard F2792. 2012. Standard Terminology for Additive Manufacturing Technologies. In ASTM F2792 – 10e1. West Conshohocken, PA: ASTM International.
Photo 1: Bronze-aluminium turbine blade manufactured using LAM (Laser Additive Manufacturing).
Photo 2: Head used for laser additive manufacturing via LMD (Laser Metal Deposition) or DED (Direct Energy Deposition).
Head of R+D+i