Q & A – Rapid Prototyping Center at University of Louisville Discusses Advances New Materials and Methodologies for Additive Manufacturing
Interview with Tim Gornet, Manager, RPC Operations, Rapid Prototyping Center, University of Louisville
Tim Gornet, Director of the RPC details prototyping, and trends in design software improvements and the need for standards within the industry.
Tim Gornet has been active in the additive manufacturing (AM)/3D printing field since 1988 when he ran an SLA 250 at GE Appliances. He is Past President of the Additive Manufacturing User’s Group (AMUG), founded the Selective Laser Sintering User’s Group and served as president for three years, has been a board member for the Society of Manufacturing Engineers Rapid Technologies and Additive Manufacturing group and was recognized as one of the “Top 25 Most Influential People in RPD&M” by the TCT Magazine. He is a frequent contributor to the annual Wohlers Report and presents at numerous industry and academic conferences on AM. His research is in the area of polymer sintering and previous work includes pioneering the use of the Melt Index for determining powder quality and developing a multi-zone heating system that has now been commercialized. Recent funded research includes several ONR/AFRL SBIR/STTR projects on unique polymer laser sintering materials and high temperature polymer applications as well as development of new materials and processing parameters for Direct Metal Laser Sintering. In addition, he has led polymer laser sintering research programs with Boeing for novel aerospace application.
AMI: Could you briefly sketch out the history of your organization’s involvement with additive manufacturing?
GORNET: Our university started up our rapid prototyping center in 1993 with laser sintering. We’ve been around this technology for a very, very long time; long before the mainstream media could even spell 3D printing. Within our center, we operate in two ways. We do work with industry on applications. We also do basic research: how can we take this 3D printing technology to the next level, whether that’s via software, hardware or controls.
AMI: Where does your organization fit in the additive manufacturing ecosystem?
Gornet: When we first started in 1993 we were just exposing people to the technology, because there were so few machines. We were trying to get people to understand how to incorporate this into their design cycles. Now 3D printing has pretty much permeated the design world, at least for making prototypes, so we’re trying to take this to the next level of using 3D printing for production of end-use parts. We work with companies on evaluating new methodologies and new materials and new developments that will allow them to use 3D printing to produce those end-use parts.
AMI: Do you do that on a one-time basis, or do you have a continuing relationship with these companies?
Gornet: In many cases we have continuing relationships; we’ve carried on with a number of companies for many years. We’ve worked with Boeing for about twelve years, looking at opportunities for 3D printing in the aerospace industry.
AMI: Focusing on technology, what is the biggest challenge (or challenges) in the additive manufacturing space today?
GORNET: Right now you’ve got two things. One is the incredible thirst for knowledge about these technologies and for people who are knowledgeable about them. The growth in sales of equipment, in particular the sales of the metals machines, has far outrun the number of knowledgeable people available to run them. The other thing is that most of these machines are what is called “open loop control.” We need to better understand the basic physics of 3D printing and implement control schemes so that the equipment is much more production-ready, where it won’t require someone with a master’s degree in engineering to get good parts off of these machines.
AMI: Putting on your forecasting hat, what do you think the biggest technical challenge will be in 3-5 years?
GORNET: One big challenge I expect will be better design software. 3D printing has the capability to build new geometries that aren’t available through today’s manufacturing technologies, but it is really very awkward to fully implement that capability using today’s design software. Most of today’s design software is meant for use with traditional manufacturing processes, such as machining, injection molding, casting, and sheet metal work. So the tools are really tailored for these traditional processes. With 3D printers, we have pretty much unlimited geometry capability, but the ability to utilize it is really being held back by software that isn’t designed to take advantage of such capabilities.
AMI: From a business perspective, what is the biggest challenge facing the additive manufacturing space?
GORNET: On the metals side, looking at making production parts, the biggest challenge is being able to certify that the processes are repeatable. You want to make sure that when the part comes off the machine that it was run correctly, that you have a certification sheet that you can give to someone that says that this was built correctly and will have the correct mechanical performance characteristics. If you start putting metal parts in mission-critical applications in biomedical or aerospace designs, for example, you need to make sure that what comes off the machine is what was intended.
AMI: What changes will be necessary to achieve this certification?
GORNET: Today we have equipment that is open-loop control rather than closed-loop control. Very few pieces of additive manufacturing equipment have any type of true monitoring capability built into them, to verify that each layer is being laid down correctly. When you utilize additive processes to create parts with novel geometries, this monitoring on a layer-by-layer basis becomes critical, as you are likely creating parts where it may be difficult or impossible to inspect them easily. So you need to make sure that the machine or the equipment attached to the machine is capable of monitoring the quality of the build as it occurs, and to make changes as necessary on the fly to ensure that you are creating a quality product.
AMI: How well understood is it today exactly what the machine should be monitoring in order to ensure that quality?
GORNET: It’s not as well understood as we’d like. There’s a lot of research being funded by NAMI, which has been renamed America Makes, into the basic physics of additive processes. You really need to understand the base physics of the problem. If you start off with a metal powder and you change its phase by melting it and then it re-solidifies, you have to understand those processes completely to be able to simulate them so that you can get a good understanding of how to control the machines in the first place. Developing this level of understanding of the physics of additive manufacturing is one of the main things that will have to change in the next 3-5 years to really allow these technologies to become much more pervasive in the manufacturing environment. The alternative—something like building a large number of your new parts and subjecting them to destructive testing to see if your additive process has produced sufficiently high quality products for your application—simply costs too much money and wastes too much time to be practical in more than a small number of cases.
AMI: How pervasive is this technology in metal manufacturing today? What kind of base are we going to be coming up from?
GORNET: GE Aircraft Engines just bought a company with just over 20 machines. I’d say the next closest company may have only 4 or 5. If you look at the total number of machines that have been sold, especially in metals, there aren’t that many out there.
AMI: It appears that this industry has been constrained somewhat by coordination problems requiring the cooperation of multiple firms—for example, it would seem harder to establish certification processes without sharing a lot of engineering data. Do you agree?
GORNET: That’s true. The majority of the suppliers of this equipment are relatively small companies. They don’t have the resources to develop all that data. You have early adopters that have spent a lot of time and money on their own to develop that kind of data. They are very reluctant to share that information, and I think very reasonably so. They want to keep ahead, and use what they’ve learned to develop a competitive advantage. As I said, there still aren’t that many machines in existence, so it’s difficult to take a machine out of use and have it just run test coupons to prove out the technology and establish the appropriate manufacturing parameters.
AMI: Are there examples of these problems that are being solved by multi-firm cooperation?
GORNET: Sure. Look at ASTM, the international standards organization—they have an active program, ASTM F42, which is tasked with developing standards for additive manufacturing. They have developed several standards and are working on others. It is, however, an entirely volunteer organization, so the development of these standards doesn’t happen very quickly. You have people from a large range of organizations taking part who are trying to ensure that the resulting standard will be fair and equitable to all groups. So that is a rather labor intensive and slow process.
AMI: How do you think this industry will evolve from here?
GORNET: We’re really at the cusp of what will happen in the 3D printing industry in the next five years. There are a number of relatively small companies that are involved in building these technologies today. But with the huge increase in the number of people that are interested in this process you are starting to get a lot of interest from larger corporations. Bigger companies with bigger R&D budgets will start purchasing some of these equipment manufacturers and developing their own equipment. With the expiration of certain patents, I’d be surprised if you didn’t see this happen sooner rather than later.
AMI: If a lot of the new technology is coming from small start-ups, as I’ve heard, will that consolidation stifle the pace of innovation?
GORNET: I believe the people who purchase and run the equipment often actually know more about it than the people who manufacture this equipment. The majority of development work in the business is being done by the end-users of the equipment. So I’m not too worried about that.
AMI: Are there intellectual property issues that additive manufacturing will raise?
GORNET: That is an issue which people will have to look at. If I buy a piece of artwork and I laser scan that, I can create a file that anyone can download and use to reproduce it. I think this is going to be somewhat similar to the lessons that the music industry had to learn when confronted by all this digital data. On the other hand, the degree of collaboration and co-collaboration that these digital technologies allow is very impressive. If you put a design out in the public domain, someone else can modify it and put it back out. There are companies that are making money in open source type applications, and doing quite well. Because this will open up the design world for a lot of people, we may have to rethink our ideas on this stuff. I’m not for piracy of anything, but in some cases this open-source approach can allow people to get access to designs that they otherwise wouldn’t get at all, including for rare spare parts, that sort of thing.
AMI: Do you see new business models arising from the use of additive manufacturing?
GORNET: I think the additive technology will allow people to manufacture items profitably at much lower volumes. There’s a big missed market in certain areas today. In a lot of industries or applications, you can make items in batches of one or two, or in batches of millions. I think there is a big missing opportunity in running batches of the three to twenty-thousand or twenty-five thousand range that additive technology will allow you to address.
AMI: Do you see an opportunity for 3D printers in “mass customization”?
GORNET: Look at Nike on their NFL Combine for last year. There are several YouTube videos. They built cleats for the NFL Combine players that were customized for each player. They made modified cleats for each player on a 3D printer.
AMI: I’ve heard that much additive manufacturing innovation for any particular industry vertical like aerospace can come from different industry verticals, like healthcare. Are there any industries that you follow closely to keep up to date on to possibly apply to other applications?
GORNET: The early adopters of new materials technologies almost always tend to be in aerospace, biomedical and sporting goods. There are a lot of companies that look at new developments in all three areas for the new ideas.
AMI: Are there any other technologies that additive manufacturing should look to in order to see how the business is likely to evolve?
GORNET: One is inkjet printers. Sales of inkjet printers exploded when people got a low-cost way to feed them information, which was from consumer digital cameras. People started buying color inkjet printers so they could print their own snapshots. Now of course people mostly use smart phones or Facebook postings to show their pictures to other people. If people want to print out their digital photos, they upload the files to Walmart or CVS. I think something similar may happen with additive manufacturing. As soon as there is any easy way to get information to a 3D printer, and it becomes easy to run the equipment, I think you may see use of additive technologies explode. I think such a development could also completely revolutionize logistics. It is much cheaper to ship data across the Internet than it is to ship goods around the world. Could this technology allow you to de-centralize manufacturing and build on demand locally, rather than build in one place globally and ship them around the world? I guess we’ll see.