It seems that every week we read about yet another revolutionary use case for additive manufacturing – whether it be organs, stem cells, rocket engines or even food. As the industry explodes, however, it becomes increasingly difficult to map out its trajectory.
A prime example of this diversity is the Direct Digital Manufacturing Lab at the Georgia Institute of Technology, whose research covers everything from medical implants to jet engines. Dr. Suman Das, the lab's director, spoke with Digital Manufacturing Report about the state of digital manufacturing, predictions regarding its future, and where his research fits within this changing landscape.
The area of digital manufacturing that has received the most media attention within the last year or so is additive manufacturing – Das' area of focus. Naturally, his first prediction dealt with this industry, claiming that within the next five years we will see three types of 3D printing users emerge.
At one end of the spectrum, Das foresees a growing number of 3D printing hobbyists who have invested in a $2,500 to $20,000 printer, and may even make it their business by opening up a small shop. At the other end, will be deep-pocketed companies investing in custom, proprietary additive manufacturing infrastructure costing upwards of $1 million per machine, meant to give these organizations an edge in the marketplace.
The category that is perhaps most indicative of 3D printing's rise in popularity will be that of medium-to-large-size businesses who hope to jump on the 3D printing bandwagon. Whether it is a company like Staples who offers 3D printing services in their office supply stores, or an organization investing in additive manufacturing equipment to more efficiently manufacture their goods, we've already seen this category beginning to emerge.
To meet the materials demand of this growing market, Das added a fourth and final factor to the additive manufacturing equation: a boom in metal powder and other specialized materials supply chains, without which industry growth would not be sustainable.
Putting aside additive manufacturing, Das noted that digital manufacturing as a whole will see an influx of new (but familiar) machines. Because manufacturing infrastructure patented in the late 80's and early 90's will soon see their patents expire, organizations waiting on the sidelines will be able release their versions of these machines within the next few years.
What will be the final outcome of these changes in machines and companies? According to Das, it will be people. Just like software innovations in the music recording industry let amateur musicians find a fan base without going through record labels, the same might come true for the manufacturing industry.
“Because of the cloud, you are going to see collaborative design and collaborative manufacturing. But you're also going to see a lot more artistic people, a lot more inventors jump in and they're going to produce very novel designs.”
Medical Implant Innovations
As for industry-specific predictions, that's where the research being conducted at the Georgia Tech's Direct Digital Manufacturing Laboratory comes in.
With the baby boomer population coming of age, there is a higher demand than ever for knee, hip and TMJ implants, making Das' research in biomedical applications relevant for tens of millions of people.
By using digital reconstruction to establish the patient's anatomical geometry, then integrating that data into the manufacturing process, the lab is able to create a custom-made implant meant specifically for a particular patient.
But what makes these parts different than, say, a set of custom-made Invisalign braces, is the inclusion of bioresorbable polymers that provide sites for cell attachment and proliferation, and eventually tissue regeneration at the implant site, blurring the distinction between what is manufactured and what is biological.
While this technology is a topic of interest for anyone concerned with his or her health and livelihood, this is not the only field in which the lab is invested. One application estimated to have a significant industry impact that should be production-ready even sooner is Das' research in jet engines.
Bringing Additive Manufacturing to Aerospace
In order to understand why the lab's aerospace research is so significant, you have to backtrack a few years: 6.000, to be exact. This brings us to the point in history when the manufacturing process for key jet engine components was created. Despite vast improvements in component performance, the process has stayed essentially the same, resulting in a manufacturing process that aerospace engineers have found wanting.
As Das explains, “High-pressure turbine blades represent the most advanced high-temperature components that are developed, designed and built by man, despite their reliance on a 6,000 year old manufacturing process called lost wax investment casting.”
To address this discrepancy and boost the quality of manufactured turbine blades, the team looked to a laser materials processing technique known as scanning laser epitaxy (SLE), which has been developed through ongoing research at the Office of Naval Research. By selectively melting and re-solidifying superalloy powders, the team is able to produce single-crystal nickel superalloys that are not prone to crack formation or erosion on their leading tip, improving performance over their traditionally-manufactured counterparts.
Specifically, the blades are able to withstand much higher temperatures, which results in a longer lifespan. Given that each blade in a jet engine costs several thousand dollars, and each engine contains several hundred blades, the savings by prolonging each blade's longevity could remodel the manufacturing norm across the entire aerospace industry.
That being said, Das noted significant hurdles that his team will face in transitioning this technology to the Department of Defense (DoD), where he hopes it will one day help drive the next generation of fighter aircraft.
We've already seen the issues of quality assurance, certification and safety arise with regard to 3D-printed aircraft components. Because the parts are manufactured using novel materials, the industry is at a loss in determining whether the components made through additive manufacturing can withstand the same pressures as their conventionally manufactured parts.
Das says that some research has been conducted regarding component certification, but stipulates that the corporate nature of these studies has prevented the industry as a whole from acting on the knowledge gained.
“This is why we have deliberately chosen the approach to make the expendable tooling that is used to make the blades rather than making the blades themselves through 3D printing,” Das explained. “Because in that way we can say that we don't change the alloys in the blade, we don't change the method by which the blade is produced, we don't even change the material composition of the tooling – we only change the way the tooling is produced.”
With regard to his own research, these obstacles in safety and performance certification haven't had an impact yet, but Das is sure that they'll come across it in the next year or two as the technologies being developed in his lab come closer to being production-ready.