The dawn of 3D printing has generated some important innovations. Now, at the touch of a button and a printer will churn out a part for a car that hasn’t been produced for decades or a replacement for human tissue or a life-like prosthetic. As incredible as these innovations are, it seems we’ve really only scratched the surface of the potential for 3D printing.
A team of scientists and engineers at the Xerox Research Centre of Canada (XRCC), led by Dr. Paul Smith, is carrying out groundbreaking research that promises to create revolutionary new materials by merging the latest innovations of 3D printing and printed electronics.
Possible innovations included technology that allows athletes wear mouth guards that monitor their heart rate as well as levels of oxygen, cortisol, and glucose — then transmit the data back to coaches on the sidelines. Or where smart drug packages can send information directly to the pharmacy about when a drug has been taken or how a patient feels. Batteries wouldn’t be a problem — they can be printed right into the package.
To discover more, Digital Journal spoke with Dr. Smith.
Digital Journal: How has 3D printing advanced in recent years?
Dr. Paul Smith: Over the last 5 to 7 years, 3D printing went through a bit of a hype phase. Everybody wanted to 3D print. But that work was aimed at prototyping or creating little novelty objects. It didn’t really address areas that go into production capabilities, like replacing injection molding.
Right now, we can’t replace injection molding because there aren’t enough materials in play. There are maybe 30 materials we can use for 3D printing today, but there are about 3,000 that we use for injection molding. But what you can see in 3D printing is that the major manufacturers are starting to move away from prototyping and going more into industrial 3D. This would have applications in the automotive, aerospace and other major industrial sectors.
DJ: What are the most important applications?
Smith: Both automotive and aerospace are looking into using 3D printed parts. In aerospace in particular, they’re exploring 3D printing because it enables the creation of very solid structures that weigh a lot less. The idea is that with those parts, fuel consumption on planes will decrease. It isn’t that they are looking at replacing big parts like plane wings, but perhaps the inside parts of the planes that could be created with more open structures but with the same integrity that an injection molded part would have.
Another segment of the market could look at customization – maybe in medical implants. Now all of a sudden, you can have custom implants for one specific person and print it in a structure that is as solid as it would have been if produced using previous methods.
DJ: How can 3D printing develop further?
Smith: When you look at the major players, they’re really moving away from novelty objects. The dominant area right now is metal 3D for manufacturing. There’s also some work, like the work we do at the Xerox Research Centre of Canada (XRCC), in plastic materials.
DJ: Are there some materials that prove more challenging than others?
Smith: As I mentioned, metals currently dominate the field. Plastics are currently limited to materials with quite low melting points called thermoplastics. For 3D to move into the industrial field, we need to use higher melting point polymers like PEEK (polyether ether ketone).
The other issue is the strength of materials. With injection molding, the materials are robust in every direction – whether vertically or horizontally, they have the same strength. But with current 3D printing, the materials have less strength in the vertical direction – where you’re printing down – so they’re more likely to fracture. That’s not just a material issue but a challenge in the way that we deposit the materials and the way that the actual particle is made.
You need to somehow model whether a part is going to be robust when you print it. Are there going to be areas where there are holes or areas where the material would accept more stress? Modeling capabilities like enhanced CAD will be very important as we move forward.
DJ: What does your recent work of creating new materials by combining 3D printing and printed electronics involve?
Smith: Printed electronics give us the incredible opportunity to print on various form factors, because now it’s not just on silicone anymore. You can print electronics using a variety of techniques – inkjet, analog – so there’s a whole range of things you can do. Now you can take something like a pipe and print 3D and electronic parts around it.
Or you can actually print electronic components as you’re printing a 3D object. You could print a few layers of a 3D object, bring in a printed electronic inkjet head and print a circuit physically inside the object, and then carry on with the 3D printing process over top of it.
At XRCC, we look at how the conductive lines on a printed circuit can sit on the 3D printed object. The interface, or the part where the conductive metal and plastic meet, needs to be robust. It can’t just peel off. So the materials need to be compatible to create a strong object.
We also need to have new, stronger materials in this space – perhaps composites. And that’s really what XRCC has done for Xerox Corporation for more than 40 years. We’ve produced materials that go into Xerox machines with various specifications and characteristics. And we have the ability to take those materials from a concept in a lab to scale-up amounts and show that they are feasible to use in machines.
This capability is what makes research centres like ours valuable to the industry. We make powders and materials. We have the ability to customize them, make them with the right specifications and produce a consistent product from batch to batch. And that’s what the industry needs right now – batch to batch consistency, a variety of particle sizes and particles that flow correctly, adhere to each other and melt at the right temperatures.
DJ: What types of 3D printers did you use?
Smith: We use a whole range of printers – SLS, SLA and even some FDM printers. I think a favourite approach right now is in areas like SLS in powder technology because that’s where we have a lot expertise. But we don’t limit ourselves to one kind because the field is unlimited and we need to be able to explore different materials for different printing techniques.
DJ: What were the greatest challenges?
Smith: To be honest, there are a whole host of challenges. There are technical challenges, but we can work on those. The big challenge we’re looking at is where to apply these techniques first. What’s that market entry point? Because to some extent, 3D printing and printed electronics won’t completely replace something we already have. Instead, it’s going to create a new market niche. So we’re focused on uncovering what that minimum viable product would be for the very first application. What is a simple way to show that this is feasible, that it has the right cost structure, that it provides new capabilities that customers want? It’s a challenge to figure out an offering that customers are excited about or that solves a problem they have and get it out there in a reasonable time in the right cost domain.
DJ: What types of applications will these new ‘smart’ materials be used for?
Smith: There’s a whole range of applications. In construction, 3D structures with attached sensors could be integrated into buildings or bridges to monitor strain. Or in the aerospace industry, 3D printed objects could have similar types of strain sensors or ones that detect wind speed or torque. In the Internet of Things (IoT) in general, printed electronics can play a role in smart packaging and smart textiles. The technology opens up areas that we couldn’t do with either conventional electronics or injection molding capabilities.
