3D printing is rapidly moving into mainstream manufacturing.
Wohlers Associates, which publishes the additive manufacturing industry’s definitive annual market report, estimates revenues from products and services in the 3D printing industry at more than $2.2 billion last year, and more than 28 percent of that is tied to the production of parts for final products.
Currently, additive manufacturing makes most sense in areas where complex, low volume or customizable parts are needed, such as aerospace or orthopedic implants. Improved patient care, increased profits, and reduced environmental impact are some of the benefits.
GE, the world’s largest supplier of jet engines, calls additive manufacturing the “next chapter in the industrial revolution,” and projects that by 2020 GE Aviation will manufacture 100,000 parts on 3D printers. The company estimates that printed parts could help reduce the weight of a single aircraft engine by 1,000 pounds, leading to significant increases in fuel economy and reduced CO2 emissions.
Additive manufacturing often allows engineers to be more creative in their designs and makes working with tricky but benificial materials like Titanium an option.
Titanium is low density, high strength, corrosion resistant, and biocompatible – ideal for use in both the aerospace and implant industries. But its cost and the degree of material waste in traditional manufacturing often make it an impractical choice. 3D printers that can build metal parts in a virtually waste-free process are increasing the number of manufacturing scenarios in which titanium makes sense.
Much of 3D printing’s potential in manufacturing comes from what is arguably its best asset: virtually unfettered design. Complex parts print as quickly as simple parts and, because there’s no need to build specialized tools or molds for casting, new designs aren’t hampered by traditional manufacturing constraints.
There are some limits. In designs that include very narrow internal channels, excess material can get trapped during production and become difficult to remove. Also difficult to remove are the supports that some parts need to hold them in place during the build process.
But in most cases designers can take advantage of the flexibility 3D printing offers. Parts can be geometrically optimized for a high strength-to-weight ratio, designed to include functional components or, in the case of orthopedic implants, custom made to fit individual patients.
When replacing joints for hips and knees, surgeons usually have to work with off-the-shelf parts that don’t fit all, then take time in the operating room to chisel and shape the patient’s bone to fit the implant. With 3D printing in titanium—desirable for its strength, lightness, and biocompatibility—it’s possible to scan a patient and use that information to create a CAD file, then print replacement joints and bones that are a perfect fit. Though only a handful of surgeons currently offer printed implants, early results show reduced recovery time and better long-term pain relief thanks to the improved fit.
For some patients, 3D printed bones and joints offer a treatment option when there is no other. An 83-year-old Belgian woman was the first person in the world to receive a custom-printed titanium lower jaw. Her age made her ineligible for traditional reconstruction, which requires up to 20 hours in surgery and weeks in the hospital. The woman’s 3D-printed jaw took just four hours to implant, and she was able to speak and swallow the day after surgery – milestones that usually take weeks to reach.
Currently, only a few makers of 3D printers, including 3D Systems (United States) EOS (Germany), and Arcam (Sweden), produce machines that can build parts out of titanium and titanium alloys.
“In orthopedics, we have several clients in volume production,” says Magnus René, president and CEO of Arcam. “Today, around 2 percent of all acetabular cups [used in hip replacements] are made by Electron Beam Melting.”
Electron Beam Melting is proprietary technology used in Arcam’s 3D printers. Most additive printers that build metal parts use lasers as a heat source, but the process is the same. Thin layer after thin layer of metal powder is spread across a build platform. For each layer, targeted heat is applied to melt specific areas, fusing them and building up the object to the exact geometry defined by a CAD model.
“The technologies are overlapping,” René says. “Typically, lasers are good for small parts where productivity is not so important, while EBM is good for larger parts where productivity is important.”
The advantages of 3D printing metal parts have prompted GE to lay out the most ambitious additive-manufacturing plan to date: printing critical fuel nozzles for a new aircraft engine rather than casting and welding them.
Traditionally, each nozzle is made from 18 parts welded together. With additive manufacturing, each part is built up as a single piece. The end result is 25 percent lighter and five times more durable than its predecessor.
Nineteen additive fuel nozzles will be installed on every CFM LEAP engine, and to date more than 4,500 of the engines (developed by GE Aviation and the French aerospace company Snecma) have been ordered. GE estimates that it will begin making the fuel nozzles in 2016, with plans to ultimately print up to 35,000 nozzles a year.
According to a recent report by the McKinsey Global Institute (MGI), using 3D printers to build parts can cut product costs by 40 to 55 percent through the reduction of tooling costs, handling costs, and material waste. The aerospace industry also reaps fuel-cost savings and environmental benefits.
EOS, a German company that offers additive-manufacturing machines and services, teamed up with Airbus Group Innovations to look at the environmental impact of 3D printed parts. It studied the lifecycle of nacelle hinges (used in jet-engine housings). Comparing hinges that were cast in steel in the traditional manner to hinges that were produced by laser sintering titanium, they found the greatest environmental impact was in the parts’ use phase.
CO2 emissions over the whole lifecycle of the hinges were reduced by nearly 40 percent via weight saving that resulted from an optimized geometry, and, most significantly, using the additive method to build the hinge could reduce the weight per plane by 10 kilograms.
With time, advances in technology are expected to improve the output speed and resolution of 3D printers, expanding the use of additive manufacturing. Technology being developed at the German based Fraunhofer Institute, for example, already shows the potential to quadruple printing speeds for metal objects.
The production of parts for use in final products is 3D printing’s fastest growing segment, with a 60 percent annual expansion rate. MGI researchers predict that by 2025 there will be a $470 billion market in 3D-printed transportation parts, and a $300 billion market in medical implants and tools.
The overall potential economic impact of additive manufactured parts that go into final products: $100 to $200 billion annually by 2025, by which time some 30 to 50 percent of complex, low-volume parts could be 3D printed.
Image courtesy of GE Aviation