Applications for metal 3D printing technology
Additive Manufacturing / metal 3D printing is an enabling technology, meaning that it is one of a class of technologies that has a wide range of uses in multiple different sectors, and can be applied to drive radical change and leaps in the performance and capabilities of the user. Identifying the right applications for metal 3D printing can be challenging, as there are often unique cost, performance, and supply chain considerations involved in the decision to use an AM process.
The advantages of AM for a particular part, and the reason for adopting AM, will differ between applications and their sectors. Often, just transferring an existing design from another manufacturing technology to metal 3D printing will prevent the full benefit of AM from being realised. However, there are many instances where AM processes are beneficial and should be considered as a technology of first preference. These include:
- Prototyping and modelling for mass production
- One-off final-use products
- Short-to-medium runs of small-scale parts that do not warrant a large upfront investment in tooling
- Lightweighting applications, where a reduction in final part weight is beneficial, such as for aerospace or electric vehicles
- Consolidation of multiple different part components into one manufacturing process which reduces supply chain management, touch labour for assembly, and also potential failure points, such as welded joints or riveted structures
- Complex designs where there is a need for a high surface area to volume ratio, or complex internal channels that traditional tool-pathing is not capable of, such as conformal cooling for moulds or heat exchangers
- Personalised or customised products where a design can be templated and adjusted to personal requirements, i.e. medical devices.
Medical applications for metal Additive Manufacturing
The medical industry has been an early adopter of both polymer and metal AM technologies. In particular, an increasing number of medical implants are being fabricated via metal AM processes. Currently, standardised implants are being manufactured via AM, with the advantages being that the design enables a lighter weight implant and a more optimum surface area to volume ratio for osseointegration (bone in-growth) and, hence, acceptance of the implant by the body.
There is an increasing focus on the additional ability, afforded by AM, to provide personalised implants for patients, particularly where a patient’s presentation is complex. Stryker is one such company that is developing the ability to use patient computed tomography (CT) data of bone tumours to develop a conformal toolpath for tumour removal and generate a design for a personalised implant.
This latest development is a good example of an industry initially accessing some of the advantages of AM, and, once familiar with the process and comfortable with its qualification, accessing more of the advantages of AM.
Aerospace applications for metal Additive Manufacturing
Additive Manufacturing is arguably the ideal production method for numerous aerospace applications, particularly where lightweighting and part consolidation are high priorities. However, safety is the highest priority in this sector and it can take a long time for new manufacturing methods to reach the shop floor, even when companies are constantly searching for new ways to cut high material costs and reduce component weight.
A branch of the aerospace industry that has successfully adopted AM technology is the space sector. Here, Additive Manufacturing is being used to great advantage, especially in the production of satellite and rocket parts that bring down the cost of manufacturing and open up new applications that are not possible to produce by any other method.
One such case is the aerospike rocket engine. When first conceived in the 1950s and later tested by NASA in the 1980s and 90s, the project was put on hold, as effective production was not possible. Today, this high-performance rocket engine is being actively developed by Spain’s Pangea Aerospace and Aenium Engineering, with an AM version built from a copper alloy, developed at NASA, now at the hot-fire testing stage.
Automotive applications for metal Additive Manufacturing
The automotive industry is undergoing many changes, with regulations and demands for greater sustainability and electrification driving innovation.
Metal Additive Manufacturing is a proven solution. However, the technology still has a way to go when it comes to bridging the gap between prototyping and production in the automotive industry. This is more often due to the cost of high-volume mass production, where there are alternative, more established manufacturing routes. But competing with these mass-production routes is not where the advantages of metal Additive Manufacturing stand out just yet.
Where it can shine in the automotive sector is with the shorter-run, performance applications. One automaker pushing the boundaries of AM is the recently established Czinger Vehicles. The company’s Czinger 21C hypercar incorporates over 350 AM components in the vehicle’s structure, suspension, brake systems, drivetrain and more.
Although most automakers do have in-house metal Additive Manufacturing capabilities, these are often only for prototype parts. Some, however, are now looking more seriously at how AM can be incorporated in higher volumes. BMW, for example, has reported success where, together with the twelve members of the Industrialisation and Digitalisation of Additive Manufacturing (IDAM) consortium, a digitally connected, fully automated Additive Manufacturing line, specifically for series production of automotive components, has been established at the BMW Group Additive Manufacturing Campus in Oberschleissheim, Germany, with a further production line located at GKN Powder Metallurgy’s facility in Bonn.
In this facility, a fully automated driverless transport system is used to carry mobile AM build chambers between modules in the IDAM production lines. Further automation sees processed metal powder delivered to workstations for preparation, and post-processing of the additively manufactured components is conducted automatically at specially designed stations.
Other applications in the automotive sector include the replacement of parts used in vintage or rare vehicles, where spare parts are increasingly hard to source. AM can also be used to repair broken or damaged parts and replace the need for costly new tooling, which would be uneconomical for such short runs.