There has been a great deal of investment in additive manufacturing with metals, but the technology still has a way to go before it is widely used, experts told an audience attending a 3D printing panel discussion at Photonics West. Jessica Rowbury reports from the show
The 3D printing market could be worth $550 billion a year by 2025, according to a recent report by Mckinsey Global Research. The figure was quoted during a panel discussion on 3D printing at the Photonics West conference and exhibition, which took place in San Francisco from 10-12 February.
Sometimes referred to as the ‘third industrial revolution’, 3D printing has garnered an increasing amount of attention in recent years. But, are the market forecasts realistic, especially concerning printing metal parts, and what does additive manufacturing mean in terms of opportunities for the photonics industry?
The benefits of widespread adoption of additive manufacturing are clear, according to Reinhart Poprawe, managing director of the Fraunhofer Institute for Laser Technology (ILT). He commented during the discussion: ‘The vision is to just be able to push a button and to get what you designed in the original material… a production chain that has no tools involved, practically no semi-finished products. The vision is to have just the powder, the computer and the button.’
However, concerning the additive manufacturing of metal parts, ‘there is a steep gradient’, Reinhart told the panel, in where the technology might one day be and where it is today.
Although in some cases it can be economically viable to print metal parts when the volume is less than 1,000, Reinhart said, 3D metal printing is not close to reaching the level of plastics, where end-users are adopting the technology to manufacture their own parts.
‘In polymer applications we talk about a business to consumer market, but for metal we don’t see that for many years, because the processes are so complex and so expensive,’ Reinhart commented, adding that a differentiation needs to be made between polymers and metals.
Developing ways of making metal printing accessible to end-users is a focus of several big players in the field, according to Jim Williams, vice president of Aerospace and Defence at 3D Systems. ‘Baker Botts, certainly 3D Systems, and Statysys have opened up the whole idea of open source,’ he said. 3D Systems has teamed up with Penn State University and HoneyWell in an effort to develop an open source AM system, and mentioned US government-funded programmes addressing the possibility of entry-level 3D printing machines.
Indeed, a lot of money is being invested in additive manufacturing, and it is reaching more than just the companies specifically involved in the area. ‘$500 million of venture capital has gone in… in the last 18 months,’ John Dexheimer commented, president of Lightwave Advisors, a financial consulting firm that works closely with the technology sector. ‘It’s going into materials, its going into software tools, its going into metrology − so I think that’s an exciting thing that there is an ecosystem to address both specific products and then all of these tools that are needed.’
A question concerning quality assurance and testing was raised during the discussion, addressing how 3D printing compares to conventional types of manufacturing that already have well established metrics for analysing quality.
According to 3D Systems’ Williams, there is a large effort from system manufacturers to both develop new methods and take advantage of existing techniques to ensure quality. ‘We’re looking at the micro-structure, looking at ways of processing where we can have closed-loops systems that allow us to detect errors and correct errors in situ… that’s a big effort that’s underway worldwide,’ he said. ‘I think we’re surrounding this from all sides, trying to find proactive ways, and then using traditional reactive ways to really know that what we’re putting out there is meeting the requirements.’
Fraunhofer ILT’s Reinhart stated that in the future, manufacturers could tailor the laser parameters to each process, which would not only ensure quality but improve it. ‘[Manufacturers could] make use of this flexibility [of additive manufacturing], and tailor the grain sizes, tailor the material to the production process. If you look at what has happened in the past, for turning steel, cast iron, cast aluminium… they all tailored it to the process. None of that has happened yet in additive manufacturing,’ he noted.
He described the only case he knew of where additive manufacturing has been tailored to a specific process − the production of scandium alloys. If three per cent of scandium is added to aluminium, lasers can be adjusted to solidify the part in a very short timescale. ‘We get an increase in tensile strength of almost a factor of two − this is amazing,’ he said, adding that this concept could have a huge impact on metal manufacturing, but more data collection and standardisation is needed.
Testing is one area in particular where Dexheimer sees a large involvement from the photonics industry. ‘It was just announced that EOS [a large systems supplier for the additive manufacturing of metal parts] has integrated in some optical tomography sensors to embed in its process. That’s some very active research that I’ve picked up on. I think this area of optical imaging, collecting data, creating this feedback loop − that’s another area where the photonics community really has a great deal of contribution.’