I was asked last week to take part in a video interview with the FT about the new world of 3-D printing. There’s been a lot of hype in the media about the subject as there is a sense that the ability to print any object that you want has the ability to change the manufacturing landscape.
The reality is that 3-D printing, or additive manufacturing as it is known, is but another process in the engineering toolkit and it has some excellent applications and benefits, but also has some limitations.
It’s a process that’s been around many years. 10-15 years ago we were running a whole suite of 3-D printers at Jaguar, using the stereo lithography process (SLA) and selective laser sintering (SLS) of nylon making first-off prototype models and functional parts. As time has passed the equipment has come down in cost and now entry level machines are even affordable at the hobbyist level.
Using these affordable machines may enable you to make a replacement knob for your microwave, but it’s not going to be able to 3-D print the whole machine.
Even here, the limitations of the printing process are evident. The strength of an SLS part will not be the same as an injection moulded original – so your digitally crafted 3-D knob may not last as long as the original!
The 3-D process can be used with metals. Here the process uses lasers or electron beams to melt powdered metals in an additive way, building up a part layer-by-layer. This process can produce parts of great complexity, even to the extent of making something which could not be made through any other process. This has a distinct advantage in that very complicated parts can be produced in one piece using the minimum amount of material.
It can also free up the design engineer to produce a super-minimalist component where the material is only added where it is needed for function or strength; a great example of this is the fan cowl door hinge developed by the GKN/Airbus team and shown in the FT video. This gives you a glimpse of the typical applications that are being explored.
Like the plastic parts there are limitations though. It’s not yet possible to replicate certain conventional metal forming processes such as forging. This long established process, imparts valuable structural characteristics to the material, making for a tougher and more impact resistant part. These characteristics are not yet achievable from the 3-D process but, for sure, will evolve over time.
Short term, real world industrial uses for the process are in medical devices (think hip joints and implants) and in the remanufacturing of high value components.
With our industrial partners we are developing a whole range of additive manufacturing processes within the High Value Manufacturing Catapult, exploring how they can be harnessed to add value in the UK.