General Electric has printed a mini jet engine and tested it at 33,000rpm.
Engineers at GE said that the goal of the project was to build an engine made almost entirely out of 3D-printed parts. The technique, also called ‘additive manufacturing’, uses lasers to fuse thin layers of metal on top of each other..
Traditional ‘reductive’ manufacturing methods typically cut designs out of larger sheets or blocks of material to create the finished shape, a process that can waste up to 90 percent of an expensive piece of metal alloy. Additive manufacturing has less material waste and more precision that allows complex mechanisms to be built and assembled in one step.
‘There are really a lot of benefits to building things through additive,’ says Matt Benvie, spokesman for GE Aviation. ‘You get speed because there’s less need for tooling and you go right from a model or idea to making a part. You can also get geometries that just can’t be made any other way.’
The Federal Aviation Administration (FAA) in the United States recently approved the first 3D printed component for a version of the GE90 jet engine.
Other aviation manufactures have used additive techniques to make aircraft parts, and as reported in the March/April edition of Flight Safety Australia, 3D printing specialist Amaero caused a sensation at the 2015 Australian International Air Show when it revealed a 3D-printed jet engine.
But 3D printing experts are concerned about how additive technology may give rise to the threat of counterfeit and bogus parts.
CASA policy (technical) adviser Dr Stephen Turner says ‘3D printing has the potential to make this problem much worse,’
Dr Turner expects the leading edge of 3D printing adoption will be sport aviation, experimental aircraft and warbirds. ‘When the parts for ageing aircraft are ever diminishing, it becomes an ideal situation to develop and 3D print replacements.’
His fear is that temptation may run ahead of the technology..
‘The issue of concern is looking at each example of the product as a prototype. Prototyping is different from production and there are consistency and replication issues with 3D-printed parts,’ he told Flight Safety Australia.
You can read more about the potential benefits and threats to aviation of 3D printing in Leaping off the page.