By David Cullen

A common question I get from people who are evaluating Additive Manufacturing (AM) for their application revolves around materials. What materials are out there?; How do AM materials compare with conventional manufacturing materials?; How do I decide which AM material to use?

In other words, people want to know how far AM materials have advanced, and if – or better yet, how – they can start benefiting from the advantages of AM.

I’m not the only one fielding these questions; AM experts across our technology portfolio at 3D Systems are responding to these questions on a weekly, if not daily, basis.  With that being the case, we decided it was time to have this conversation more broadly to better connect you with the information you’re looking for. To do that, we are banding together to bring you “Material Information” – a blog series on the current state of AM materials for production, along with our insights on what to expect down the line.

We are breaking this series down by 3D printing methodology, starting with Selective Laser Sintering, to be followed up by Stereolithography and Figure 4.                                                    

So, let’s get into it.

This SLS part (DuraForm PA) spent 500 hours inside a running engine. Although this was not a non-stop run, this amount of time in hot oil is a testament to the material's rugged performance. Image courtesy of Briggs & Stratton.

Why is Selective Laser Sintering a good choice for production applications?

Selective Laser Sintering (SLS) is a strong choice for production because it is compatible with such a versatile, performance-focused range of materials. Beyond material selection, SLS is great at delivering complex parts: cost-effectively, at an accelerated rate, and with reduced labor requirements. As a powder-bed process, SLS is self-supporting, which can be a big advantage for consolidating assemblies into monolithic parts to minimize post-processing and maximize innovation in design.

If you are interested in learning more about the SLS process, there are plenty of resources available, and we can always dive deeper in another series if you have questions you’re still looking for answers to. In the meantime, let’s get back to the topic at hand, which is SLS materials.

The materials available for SLS are incredibly robust. If I had to pick one word to describe them all, it would be functional. To fully do them justice, however, it is worth highlighting some specific SLS options to paint a clearer picture of what’s available.

SLS thermoplastics

3D Systems’ SLS thermoplastics are carefully developed to meet specific performance requirements and deliver attributes like heat resistance, impact strength and varying degrees of rigidity or flexibility.

For example, DuraForm® ProX® PA  is a popular choice for strong and durable prototypes as well as low- to mid-volume production. DuraForm ProX PA is a nylon 12 polypropylene-like material and is extremely versatile. It is a UPS Class VI capable material for bio-compatible applications, and is also food grade.

Nylon 11 and nylon 12 for SLS

Many of 3D Systems’ SLS materials are nylon 11 or nylon 12 based, and incredibly robust for that reason.

For example, DuraForm® ProX® EX-NAT is a nylon 11 that offers excellent impact and fatigue resistance, and is a great choice for applications requiring durability and longevity. It is also resistant to fuel and oil, making it an ideal candidate for automotive simulations and other applications where exposure to hydrocarbons is likely.

3D Systems’ nylon SLS materials are available in both natural and black options, giving users flexibility in the appearance of their printed parts. Our DuraForm® ProX® EX BLK nylon 11 material is consistently black, making painting unnecessary for color purity. Similarly, our natural nylon options are consistently uncolored, yet receptive to dyeing, painting, and plating with very attractive results. The combination of visual and physical properties that is attainable with SLS nylon is part of what makes it such a compelling choice for so many.

Download 3D Systems' SLS ebook and material guide.

3D printing with composite nylons

A major reason demanding industries and applications turn to SLS is the range of composite materials available, and the downright abusive conditions these materials can withstand. 3D Systems offers several filled or reinforced SLS material options, including glass-filled, aluminum-filled, and fiber-reinforced. These materials are engineered to perform, and offer unique and desirable benefits.

For example, DuraForm® ProX® GF is a glass-filled composite that is well-suited for applications requiring stiffness as well as elevated heat resistance. Aircraft and motorsports parts are a good example. Another great option for high temperature applications is DuraForm® ProX® HST Composite, which is non-conductive and RF transparent, again making it a great pick for demanding applications and harsh environments. For more on what's available in SLS, also feel free to download our SLS ebook

What kinds of applications is SLS good for?

SLS parts excel in a diverse array of applications, from medical and dental to aviation and consumer goods, as well as the harsh and demanding environments of professional auto racing and aerospace.

With this rough sketch of the broad scope of SLS, it is easy to understand why it has gained traction across industries. Along with materials, its precision, tight tolerances, and large build sizes make SLS a leading AM technology for functional parts and products ranging from small clips and surgical guides to air ducts, jigs, fixtures, living hinges, and mass customized products. Realistically, any time a relatively small batch of high value parts is needed, SLS should at least be considered.

I hope you found this first installation of the series useful. If you have any questions, I speak for everyone at 3D Systems when I say we are always happy to help. Please make use of the “Contact Us” button to reach out if you want any more information.