If we look back at the evolution of buildings, bridges, transport and many other familiar objects, we can see a link between manufacturing process, materials and design. If you change one, you either have to change the other two, or at least have the opportunity to do so over time.
Additive Manufacturing (AM, also known as 3D printing) is no exception to this rule. This ‘new’ process (now over 25 years old) of manufacturing additively in layers, provides huge scope for change in both design and materials.
Taking design first, we need look no further than popular sites on the internet. New companies like Shapeways and iMaterialise, have sprung up over the last five years and can provide the home enthusiast with the scope to design and make almost any (but not every) object they wish.
We are also seeing more advanced design tools emerging on the internet. For example Digital Forming which leverages the designs and knowledge of experts for non-expert users to exploit with sophisticated tools. You can even design your own doll via MakieLab.
In the industrial context, potentially the greatest impact 3D printing will have is in weight reduction (and hence CO2 reduction) in transport systems and other accelerating objects such as engine parts. There are already many case studies in aerospace and motorsport that demonstrate the benefits in fuel and component performance. Simply reducing the mass of a commercial jet by 100kg saves 4.5 million litres of aviation fuel over its lifetime.
Materials and process
Moving on to materials, the changes are probably less obvious to the external observer, but they are no less dramatic. In the mid 1980s, you could choose just one process and one material for AM, stereolithography (SLA) and a brittle epoxy resin.
By the late 1980s, a new process, selective laser sintering (SLS), emerged which enabled tough nylon parts to be made. By the mid 1990s, there were many polymers in use and the SLA and SLS parts became more accurate and functional. It also became possible to make basic metal parts and dozens of new AM methods were being developed.
Today, metal AM enables the manufacture of high complexity parts able to withstand extreme temperatures and stresses, including those for jet engines and F1 cars. In some cases AM is even showing signs of taking over from some casting techniques.
There are now over 20 metal alloys being used commonly for AM including titanium alloys, nickel super-alloys, aluminium alloys, steels and others. New alloys are being released for use on an almost monthly basis. It is reasonable to project that by 2015, there may be a hundred or more alloys in common use and still rising.
AM is enabling substantial advances in design and materials separately. However, we are also seeing design and materials developments combining to produce even greater advances in functional performance. We can therefore expect to see increasingly exciting progress in the future.
Chris Tuck, associate professor, at the EPSRC Centre for Innovative Manufacturing in Additive Manufacturing, University of Nottingham, explains what his institution is doing to uncover the full design potential of additive manufacturing.
The EPSRC Centre for Innovative Manufacturing in Additive Manufacturing at the University of Nottingham, in partnership with Loughborough University, has set its sights firmly on researching additive manufacturing (AM) and 3D Printing for the production of multi-material and multifunctional components in a single manufacturing system.
Research within the EPSRC Centre is backed by £5.9m of funding and focuses on the investigation of new AM processes, such as 3D inkjet printing; and the required simulation, modelling and design systems to support the manufacture of end-use, multifunctional products.
Example process research in the centre includes:
- 3D jetting of electronic materials
- Reactive jetting of bio-resorbable structures 2-photon lithography for producing nano-scale
- AM structures for functionalised sensor production
These projects are coupled to design and simulation oriented research aimed at exploiting the design potential of AM. This research must acknowledge and incorporate the effects of adding different materials to components and their role in changing the overall properties of the system.
The vision for the Centre is to be able to create complete multimaterial products in a single manufacturing step, without the need for tooling or assembly operations.
The development of this new paradigm within AM will enable ever increasing function coupled with reduced product development time, with the benefit of allowing greater design functionality and potentially greater design iterations. This is in conjunction with reducing the requirement for manufacturing the millions of components or products, required in today’s high volume production scenarios.
So what of the future for AM? We could easily get over-excited about what we can do now and extrapolate overoptimistic expectations as to how quickly advances will progress.
It is better to be more circumspect. AM cannot solve all our problems, and does of course have its own limitations. Also, despite the apparently rapid rate of change, AM is not a ‘new’ technology, it is simply now coming into the public consciousness and being more widely publicised. It will take years before we can use the technology to make highly capable, multi-material objects at home.
In most cases, AM parts tend to be relatively expensive at the moment, and they are mainly comprised of a singlematerial. Surface finish can be a challenge due to the layers and powder and parts are usually size-limited, particularly for metals but we can expect all of these factors to change over the coming decade or two.
We will see home-manufacture of basic parts becoming the norm over the next few years. The volume production of high-end and even more common parts, like jewellery, will emerge in the same timeframe. Multiple material products, larger parts, lower costs, better design tools, and easier accessibility for the general public may take a little longer.
AM will certainly drive enormous change in our world, but real results will take time. If we maintain moderately positive expectations, then we can take great delight when those expectations are exceeded.