3D Printing for Manufacturing: Hype or Reality?

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1 DECEMBER 20, D Printing for Manufacturing: Hype or Reality? By Scott Evans and Sal Spada Keywords Additive Manufacturing, 3D Printing, CAD/CAM Software, Rapid Prototyping, Direct Manufacturing, Rapid Manufacturing Overview In the past, 3D printing for manufacturing, or additive manufacturing, had been primarily used as a rapid prototyping tool for plastic parts. However, the sphere of applications is expanding as use of printable metal alloys, such as tungsten and titanium, gains traction. Creating prototypes is still the dominant 3D printing has expanded beyond rapid prototyping applications. Now, there are application; however, the technology has matured to the point where manufacturers can use printers designed both for personal and professional use. As the technology it to complement or replace traditional production processes. continues to infiltrate the pop culture landscape, many have raised expectations for industrial 3D printing. The technology has applications for multiple industries and Leading manufacturers are now looking at potential 3D printing applications in multiple areas could add value in a number of different manufacturing areas. to determine where it could save time or costs. For production processes, it appears that 3D printing can provide the most benefit for manufacturers seeking to move toward smaller production quantities. More Questions than Answers Over 250,000 people viewed a Business Insider article on 3D printing, entitled "The Next Trillion Dollar Industry." In a similarly scoped article, "A Third Industrial Revolution," The Economist posited that 3D printing could provide the catalyst for the next industrial revolution. However, while 3D printing has gained widespread acceptance in certain commercial applications and clearly has the potential to represent a disruptive technology for VISION, EXPERIENCE, ANSWERS FOR INDUSTRY

2 ARC Insights, Page 2 manufacturing, manufacturers need to perform pragmatic analysis to determine what type of production processes are suited to this new technology, how it could be implemented, and at what cost. There are still challenges to overcome and questions to answer before we see widespread adoption of 3D printing. These include: Can 3D printing eliminate process steps and, if so, how many? Will the productivity improvements and other cost savings achieved be sufficient to warrant the technology investment? Will the technology eliminate (or create) bottlenecks? How much post-production finishing work would be required? Would the technology provide the required quality and life expectancy for the manufactured parts? What are the practical upper and lower limits for production runs? To evaluate the potential applicability to their operations and potentially develop a business case, manufacturers should consider the following. Eliminating Inventory Holding Costs Service and support organizations looking to reduce their inventories can often make a business case for 3D printing. This is particularly true for older products that have outlived their normal support periods. In one interesting example that illustrates the potential, Jay Leno's Garage contracted with a supplier to produce a replacement steam valve for the late night TV host s 1907 White Steam Car, part of his extensive automobile collection. The last manufacturer of steam car parts went out of businesses over a century ago, and spare parts were not to be found. To produce an exact functional replica of the steam valve, the original steam valve was laser scanned, converted into a 3D computer aided design (CAD) model, and then recreated using a 3D printer. The valve was installed and the vehicle became operational again. For machines and products intended to remain in service for a relatively long time period, 3D printing could preclude the need for spare and replacement parts inventories. Art-to-Part-Design Cycle Reduces Time to Market Part design for 3D printing is comparable to part design for machine tool manufacturing. The process begins with a 3D model, created using traditional CAD design tools. Alternatively, a part can be reverse engineered

3 ARC Insights, Page 3 using a 3D scanner to generate a CAD file. The file then needs to be primed for printing. This process step is similar to using computer aided manufacturing (CAM) software in the machine tool world to prepare the CAD files for the specific production machine and tooling used to manufacture the part. In 3D printing, CAD files are converted to the STL file format included with most CAD editing software. The 3D printer industry has standardized around the STL file format, which supports the transition from art to production parts. ARC has encountered multiple meanings for STL, including standard tessellation language, standard triangulation language, and stereolithography. Regardless, STL enables the CAD file to be spliced into multiple thin crosssectional layers via software embedded in the printer. Each successive cross-sectional layer is printed on top of the preceding one, which is why 3D printing for manufacturing is also known as additive manufacturing. While most CAD software packages provide STL conversions, this does not always produce a printable file, requiring additional modifications. STL files are displayed as a series of surfaces formed by connecting threedimensional triangles. CAD designs can lose structural integrity when converted into STL format. In the translation, gaps between triangles can emerge, and a model that is not "watertight" cannot be printed. An experienced user can fix faulty STL files, but software is also available to ameliorate this process and often is included with high-end 3D printers to eliminate the gaps. The American Society for Testing and Materials (ASTM), an international standards organization, has designed and is attempting to implement the Additive Manufacturing File Format (AMF). This open standard format would obviate the need for STL, while adding additional functionality, including representing the color and textural properties of the printed object. Benefits and Drawbacks Once the 3D model is converted to a printable STL format, it can be used to print any appropriately sized part, assuming that a suitable printing material is also available. Different printers can print in myriad materialsplastics, metals, ceramics, glass even cheese. The printers fuse or bind together a granular, powdered form of the material using a laser, electron beam, or inkjet head. Other technologies use laminates and filaments in-

4 ARC Insights, Page 4 stead of powder. Printing time is based on the size of the printed object and the specific binding technology of the printer. The relative speed and size restraints of 3D printing, coupled with the expensive feedstock for the printers, make it unsuitable for mass production. For metal parts, 3D printing's strength is its ability to print intricate designs and structures that cannot be created efficiently 3D printing technology lends itself through traditional machining. 3D printing technology to small-batch productions of highly valuable, highly complex, highly lends itself to small-batch productions of highly valuable, highly complex, highly customized parts. For customized parts. these parts, 3D printing is both faster and cheaper than traditional manufacturing. Some especially complex 3D printed metal parts last longer than their traditionally-machined counterparts, providing another justification for the technology. Around 97 to 98 percent of the leftover printer feedstock for each layer can be reused in the next layer, as opposed to traditional "subtractive" manufacturing in which 50 percent to 75 percent of the material is cut away. This significantly reduces costs for items fabricated with expensive metals, such as titanium. Because parts can be configured and adjusted using software, there is no incremental cost for printing a more complex part. Most 3D-printed metal parts require at least a modicum of finishing. The more finishing a part requires, the less value 3D can offer. 3D printing is designed to eliminate steps in the machining process, and if it can only reduce machining time in one step of the process, there is less justification for a major overhaul. This remains the major obstacle for using 3D printing in metal. In addition to eliminating finishing, printers need higher powered lasers and an increased level of automation to speed up the production process. Process Validation In industries such as aerospace, it can be time-consuming and expensive to certify a 3D-printed part and validate production processes. The resources needed to qualify the part with bodies such as the US Federal Aviation Administration often exceed the value added by 3D printing. For this reason, 3D printing is often reserved for new components. But aerospace companies are already taking notice. GE Aviation recently acquired two

5 ARC Insights, Page 5 companies specializing in additive manufacturing services. This may start a trend of in-house production of 3D-printed aerospace parts. Takeaways and Relevance 3D printing has clearly gone viral in pop culture. Community-driven websites enable users to share and download STL files in much the same manner as one can download music or movies on the Internet. Many companies have developed free, open-source CAD and 3D modeling software to complement lower cost (under $1,000) personal printers. The proliferation of personal 3D printers and products has certainly fueled speculation about potential industrial uses for the technology. Since parts made of plastic, the most commonly used 3D printing material, are generally mass-produced, 3D printing is only cost-effective to produce complex, small-batch plastic parts. 3D printing in metal is a newer development. Currently, most 3D-printed metal parts still require finishing, and 3D printers require cleaning and prepping between jobs. To be disruptive, the technology must obviate the need for additional processes in the production of a part. Industrial 3D printing can continue to expand in reach if more expensive and exotic metals become printable and the process can be refined to reduce the amount of finishing required. This would enable manufacturers to use 3D printing to make die castings (for conventional production processes) and other metal molding processes, especially ones requiring complex cooling channels. 3D printing also has tremendous potential in the medical products manufacturing industry. Most hearing aids are already produced using 3D printing. Because of the ease of customization, prosthetics is another ideal application. Also, some companies have already developed "bioprinters" that can print human cell tissues. While these tissues will not be transplant-ready, for years, they may be used sooner for preclinical drug trials. As the population continues to age in the US, Europe, and Japan, these medical applications could be vital to reduce the cost and time of procedures associated with an aging population.

6 ARC Insights, Page 6 Recommendations With new printers designed to print in myriad materials, mostly anything designed on CAD tools can be printed. There are still limitations in materials, the size of the printed product, and the speed of the process; but the technology is growing at a rapid clip, representing an opportunity for 3D design software makers. ARC also recommends that PLM software makers evaluate the technology to potentially increase the functionality of their software products. Manufacturers should explore opportunities to use 3D printing to complement their existing procedures, especially for metal parts. Even though the metal feedstock is expensive, the implementation of additive processes ultimately will reduce material usage and lower costs. This will become increasingly important as exotic and refractory metals become printable. 3D printing can play a part in JIT production strategies for low-volume production of high-value parts. However, as most printed metallic parts require post-production finishing, the justification for switching to additive processes is based on the complexity of design additive processes can achieve, rather than economics. However, as printers become larger, faster, and more dynamic; the range of available feedstocks increases; and finishing requirements for certain materials are reduced, it will become easier for manufacturers to establish a business case for 3D printing. ARC will continue to track the acceptance of this exciting new niche, but potentially disruptive manufacturing technology and update our clients on our findings. For further information or to provide feedback on this Insight, please contact your account manager or the author at sevans@arcweb.com. ARC Insights are published and copyrighted by ARC Advisory Group. The information is proprietary to ARC and no part may be reproduced without prior permission from ARC.