3D-printing project set new speed record for printing in nanoscale resolution

(Nanowerk News) The promise of 3D printing has many of us spellbound, and indeed the ability to conjure up objects on demand could completely change our lives. In homes, offices and workshops around the world, this revolution is only just beginning – mainly with equipment designed for small-scale production at a leisurely pace. Just think what could be achieved with fast, high-precision printers built for large-scale manufacturing, such as those developed by the EU-funded PHOCAM project.
PHOCAM focused on two core techniques - 3D printing for high-performance ceramics and 3D printing with ultra-high resolution - and achieved remarkable results. It improved processes so significantly that its printed ceramic parts now measure up to the most stringent criteria for high-precision engineering, and it set a new speed record for printing in nano-scale resolution.
It also managed to bridge the gap between a promising theory and a convincing product. 3D printers based on the project’s ceramic printing technology are already available on the market and in industrial use. A spin-off company – Lithoz – is handling the commercialisation.
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Two-photon polymerisation (2PP) is a technique to fabricate three dimensional structures with resolutions down to 100nm (see details of Tower Bridge).
Manufacturing in a new light
Innovations such as these could ring in a new era for the manufacturing industry. Basically, a 3D-enabled factory would be freed from long lead times and high set-up costs, and so could turn out a wide variety of products as and when required. Any manufacturable object, once drawn, could be produced at short notice.
It would also be possible to switch flexibly between completely different products, generating them in batches large or small – no need to adapt tooling or adjust assembly lines. “You just change the job file for your 3D printer,” says Professor Jürgen Stampfl of the Vienna University of Technology, who coordinated the project.
This is the theory. In practice, he explains, 3D printing today is mainly used for prototyping or very specific small-scale applications. A number of limitations have to be addressed before 3D printing could viably be used for large-scale manufacturing. PHOCAM, an EU-funded project initiated in the context of the public-private partnership Factories of the Future, set out in June 2010 to do so. The partners’ work focused on photopolymer-based techniques – where light-sensitive materials are sculpted by lasers.
More specifically, thin coats of liquid polymers are made to harden along the required outlines by exposure to light, with successive layers building up to form objects. Ceramic objects can be produced by mixing particles into the polymer, which is later eliminated. While there are other powerful 3D technologies, the partners were convinced that this approach offered a particularly high potential for the development of industrial applications.
Heavy-duty ceramics
Producing ceramic parts with suitable mechanical properties was one of the key challenges: while 3D printing techniques existed, they could not turn out objects to the required standard. PHOCAM managed to overcome this limitation. By the time the project ended in May 2013, it had developed technology that could reliably produce high-performance ceramic parts for demanding engineering applications.
How were these improvements achieved? Process chain integration, in short. “We had a consortium where we had the capability to cover the whole process chain,” says Professor Stampfl, emphasising that work on individual steps or aspects of the process would not have yielded the same results.
Meeting the need for speed
Another key consideration was speed – or lack of such. PHOCAM was determined to take high-resolution 3D printing to new heights by achieving outstanding precision at the nanoscale. However, the ability to produce objects would be of limited practical value, says Professor Stampfl, if printing them takes forever.
The partners were therefore equally determined to accelerate production, and their process chain approach proved successful again. In fact, the speeds they achieved for this particular type of technology are unprecedented, measured in metres rather than the usual millimetres per second.
Advances such as these are widening the scope for industrial applications, and they are only the beginning. Professor Stampfl is convinced that 3D technologies can play a key role in shaping the future. “If the European R&D community and industrial community get it right, 3D printing could be a cornerstone of the reindustrialisation of Europe,” he concludes.
Source: European Commission