Micromanufacturing using additive technology

Advances in additive manufacturing technology have not always led to bigger and bigger builds, as Tel Aviv, Israel-based Nanofabrica demonstrates.

The company has developed an AM platform that can produce miniaturized products and components with micron resolution features at volume.

Earlier this year, Israeli additive manufacturing innovator Nanofabrica commercially launched its micro 3D printing technology that reaches micron-level accuracy over a build envelope of 5 by 5 by 10 centimeters. The technology offers a viable mass manufacturing alternative to traditional manufacturing processes such as micromolding, the company said, and its characteristics open up the opportunity for significant innovation in product design and development.

At the macro and micro level, the additive manufacturing process, if correctly approached, can lead to fewer design iterations, less assembly work as a result of part consolidation as well as inventory reduction. After all, if little or even no assembly is required, there is also no need to carry an inventory of different components, nor for a stock of fasteners such as screws, bolts, nuts, washers and the like.

AM also enables the design and production of extremely complex geometries, with no complicated tooling solutions required and hence at no additional cost. And because no tooling is needed, designs can easily be modified, paving the way for mass customization for the first time in the micromanufacturing sector. This means that significant operational cost benefits are now attainable at the micromanufacturing level.

3D printing at the micron level brings high-volume applications within reach, as thousands of tiny parts and components can fit easily in the machine's build envelope. "The machine delivers micron precision digital innovation in every part produced," Jon Donner, CEO at Nanofabrica, said

For OEMs, therefore, unlike in traditional processing technologies, micro additive manufacturing means that economies of scale become irrelevant: Whether producing several thousand or just one component, the costs remain low. In this way, the low-to medium-volume production runs that the high tooling and setup costs associated with traditional manufacturing alternatives would otherwise have made prohibitively expensive suddenly become an affordable option.

The micro AM technology developed by Nanofabrica allows — for the first time — micron-level production with the precision, resolution and repeatability required in product miniaturization. It enables a microstructure and workpiece accuracy to be obtained that was previously only achievable with micromolding. And because it is agnostic to part complexity, it allows for the design and manufacture of hollow structures, holes, complicated interior details and atypical shapes that could not otherwise be efficiently or cost-effectively produced.

The innovative nature of the technology is also being recognized by the industry: Nanofabrica has been shortlisted as a finalist in the TCT Awards in the category Hardware — Polymer Systems. The winners will be announced in a Sept. 25 award ceremony during the 2019 TCT Show.

Freedom of design is the hallmark of AM. However, before designers can take full advantage of the benefits offered by this design freedom — at both the micro and macro AM level — they must acquire an understanding of the Design for Additive Manufacturing (DfAM) philosophy.

Currently a hot topic, DfAM demands an entirely different approach and set of skills to achieve success than Design for Manufacturing (DfM) using traditional production technologies — something that is often overlooked, especially with the current global shortage of professionals with AM design skills, said Donner.

"The shortage of professionals that can design AM parts that translate through the additive process to the successful production of end parts is a serious issue. It has developed because for years AM was used as a prototyping technology, and it is only in recent years with the move to the use of AM as a production technology that DfAM has become a concern. DfAM demands a whole different approach," explained Tovit Neizer, VP business development at Nanofabrica. "A primary design consideration with AM comes with the support structures that are needed for many additive processes — what kind, and where these are placed."

And while most AM software automatically generates support structures, developing the software to do this requires expertise and experience to create the requisite algorithms to produce them, as different AM technologies and platforms require different support structures.

Two other major benefits of AM are part consolidation and topology optimization, both of which contribute to producing lighter and more functional parts. Traditionally, complex components must be produced in various parts to make manufacturing possible, and these parts must subsequently be assembled. Assembly is especially problematic, complex and expensive when looking at micro applications.

AM opens up new opportunities for manufacturers, as it allows multiple part assemblies to be consolidated into a single part — eliminating time and costs in the process of producing a more functional result. The micro AM platform developed by Nanofabrica offers the software tools needed to allow micro manufacturers for the first time to benefit from the design capabilities presented by the use of AM.

DfAM expertise also includes an understanding of topology optimization, said Eyal Shelef, Nanofabrica CTO. Many structural components are designed with more material — and thus more weight — than they require. This, in turn, can mean increased and unnecessary loads on moving parts and compromised energy efficiency during use. Topology optimization for AM parts allows designers to specify loads. When designing parts for AM, a designer can take a traditionally shaped part, simulate where the loads will run through that part and remove the superfluous material, leaving only the load paths remaining. This not only yields weight savings, but it also results in the design and production of parts with highly efficient strength-to-weight ratios.

AM, in short, requires product designers to think differently from what they are used to. Traditional design constraints no longer apply, and complexity no longer comes as a premium. DfAM, designing within the parameters of the AM process, can invariably lead to more efficient parts, improved strength and durability, while also reducing costs and improving safety.