Whether intentionally or unintentionally, 3D printers can be tricked into creating components with defects that standard tests cannot detect. (Image source: New York University)
In the race to adopt new 3D printing and additive manufacturing (AM) technologies, engineers and manufacturers are overlooking a key element – cybersecurity.
According to a new paper, “ Manufacturing and Security Challenges in 3D Printing ”, written by researchers at New York University's Tandon School of Engineering and published in the May 2016 issue of the journal JOM, The Journal of The Minerals, Metals & Materials Society (TMS) , 3D printing carries cybersecurity vulnerabilities that can lead to potentially dangerous, undetectable defects as well as opening the door for counterfeit products.
Nikhil Gupta, an associate professor of mechanical and aerospace engineering at NYU Tandon, and one of the co-authors of the paper, told Design News that the cybersecurity risks that come with AM are far more significant that common threats we hear about today. “The number one problem is you are creating a physical object that will be used in a system,” Gupta said. “This is not like a stolen credit card number that you can change quickly to avoid damage. In this case the product is created and being used in a system.”
Imagine a 3D-printed shaft breaking while someone is driving at high speed and you start to understand Gupta's concerns. “Our emphasis in this paper was to show there could be certain small defects in materials, so small that common detection techniques would miss them, but they compromise the properties of these components,” he said. “Many people have shown [3D printers] can be hacked. As a materials scientist my emphasis was to show these tiny defects can be included that would comprise the integrity of the materials used.”
Gupta and his team conducted their research in two parts. In the first they examined the effect of printing orientation on products' structural integrity. Since CAD files do not specify printer head orientation, the researchers wanted to see if any change in orientation would have a measurable impact.
NYU Tandon researchers printed test products in three orientations and found that altering the orientation of a 3D print could have a significant impact on the material strength. (Image source: New York University)
Test products with the same geometry were printed to the ASTM D638 standard, but at three different orientations. The researchers found that altering orientation could result in a significant loss of tensile strength. Of the three orientations tested they found that one (a 45-degree orientation) was up to 30% stronger than the other two orientations. “Thus, if the original model is intended to be oriented at 45 direction for printing, a change in the printing direction can significantly lower the strength and modulus, making the part underperform compared to the design conditions,” according to the paper.
In the second part of their study, the researchers deliberately introduced sub-millimeter defects that could result in product failure between printed layers of products printed to the ASTM E8 standard. When the printed parts were quality checked using a