This article was originally published on May 1, 2014.

Some would say that 3D printing is a state-of-the-art manufacturing process. Perhaps it’s more of a coming-of-age story. Just what is it all about? Why is it important to the high-temperature thermal-processing industry? We review the past, present and future of this hot technology.

Is additive manufacturing (AM) a 21^st-century invention? Not at all. The process of “printing” solid objects through progressive layering was first called stereolithography (SLA), and it was invented and patented by Charles W. Hull in 1983. The commercialization of the process gave birth to 3D Systems, which still operates from its South Carolina headquarters. In November 2013, 3D Systems announced a $10 million investment to expand its manufacturing operations, generating 145 new jobs.

What is AM?

There are really several types of 3D printing technologies. The first is SLA, mentioned previously. For this process, a laser is used to cure a resin and build a prototype one layer at a time. Rapid prototyping is similar, but (unlike SLA) no supports are used to hold up the part (Fig. 1).

    Fused-deposition modeling (FDM) is a variation in which the printers melt a plastic filament – ABS or PLA – and deposit the plastic in layers until it creates the model. MakerBot is a manufacturer of this technology. Direct metal deposition applies to metals built up in a similar way.

    Selective laser sintering (SLS) will become, or already is, more familiar to the readers of this journal. In this technology, powdered metal is sintered using lasers. The sintering results in a solid structure one layer at a time. When a layer is completed, the structure drops so that the next layer can be built on top.

Past

Universities and large industrial companies began using 3D printing by the late 1980s for rapid prototyping. A part would often be made from a plastic material and used to fashion a part from the design material (metal). The cost of equipment and limited materials and applications prevented practical access for many companies.

    As this technology developed, particularly over the past decade, Industrial Heating has reported the news in print, in our newsletters and on our website. At least two articles have covered the technology – in May 2011 and January 2012 – and our August 2013 editorial promised ongoing coverage. Promise kept.

Present

It seems that the present state of additive manufacturing is rapid change. Much is changing to make the technology better, but let’s stay in the present for now. Improvements in technology and reduction in price have resulted in a growth of commercial applications.

    More than 50,000 3D printers were sold in 2013, and this is expected to double by 2015. Data from Wohlers Associates estimates the market for 3D printers at $2.2 billion in 2012, $6 billion by 2017 and $10.9 billion by 2021. The Freedonia group is more conservative, predicting an annual growth of 20% to $5 billion in 2017.

    There are two key 3D players in this market. They are 3D Systems (Fig. 2) and Stratasys. Makerbot, mentioned earlier, was acquired by Stratasys last August for $400 million. 3D Systems has a larger stake in metal AM. This is partially due to their buyout of Phenix Systems, a French manufacturer of direct-metal SLS 3D printers.

Foundry

There are two basic applications of this technology in the foundry (Fig. 3). The first is to use it for moldmaking. In a foundry, metal or wax patterns are used to create molds in different stages. Depending on the life of a part, this historically time-consuming step was easily justified. But what if it is a very short-run part? 3D printing can skip tooling by directly printing sand molds or cores. Very short-run or one-off parts can be produced directly on a 3D printer, assuming material requirements can be met.

Aerospace

Last year, NASA successfully tested 3D-printed rocket-engine parts. Additionally, functional components have been 3D printed and tested on the Tornado fighter jets (Fig. 4) used by the Royal Air Force (RAF). The ability to use 3D parts in maintenance is expected to save the RAF about $2 million over the next four years. For aerospace and other industries, the ability to manufacture parts when they are needed avoids storage costs or lead-time issues when a critical part fails.

    NASA has also printed tiny, wafer-like satellites that will be used to cheaply transmit research data back to Earth. Their goal is to put 3D printing into space to make astronauts more self-sufficient by printing out whatever parts they might need (think Apollo 13). A 3D printer has been built and tested that can work in zero gravity. It will be sent to the International Space Station (ISS) on a future mission (Fig. 5).

Automotive

One of the early adopters taking advantage of 3D technology was Hendrick Motorsports in the world of NASCAR (Fig. 6). Hendrick uses rapid prototyping and 3D printing to “make mistakes in plastic” to cut down on cost. They also produce some non-essential equipment such as mirror mounts for use directly on the cars.

    CRP Group was good enough to provide us with a case study and excellent photos. Working together with Magneti Marelli Brazil, their goal was to produce a fully functional intake manifold (Fig. 7) in a short time period in order to test a new design. A custom-designed material, WindformGF2.0, was utilized. It is a polyamide-based powder reinforced with glass fibers and aluminum. It was chosen because the manifold needed to resist high temperatures (to 130°C) and be fully fused to resist vacuum loss or leaks (Fig. 8).

    The benefits of this type of testing are obvious. Without establishing a manufacturing process and long lead times, new designs can be brought to life by creating functional components that can be subjected to severe testing. If a design modification is needed, another component can be manufactured using 3D technology for proof testing.

    A vehicle worth mentioning is the Urbee 2 (Fig. 9), which is a 3D-printed car (more than 50%). The Urbee folks plan to drive their car across country within the next couple of years. They hope to see the vehicle in production soon after the cross-country excursion. Depending on how many are produced yearly, the sticker price will be anywhere between $16,000 and $50,000.

    Another company, Local Motors, Inc., recently announced that it will be building its 3D-printed production vehicle during The International Manufacturing Technology show (IMTS) in September. They will build their flagship Rally Fighter from the ground up in five days over the course of the six-day show.

Empowerment, Opportunity and Ideal Applications

Through the use of 3D printers, many entrepreneurs are using micro-manufacturing to create custom products in small batches without a conventional factory. For more traditional manufacturers, 3D printing may save millions in retooling costs. Inventory of replacement parts can also be reduced or eliminated. Unexpected machine failure will no longer result in massive delays and missed deliveries. 3D printing can be used to manufacture a replacement part in very little time.

    We already discussed molds, which is an optimum application for 3D printing. Other ideal applications include parts with very specific applications. An example is dentalwork with unique requirements  (Fig. 10). Prosthetic limbs can be made for the individual’s exact size. No more off-the-shelf, poorly fitting parts.

    Another medical application involves combat surgery. Keeping sterile instruments in stock on the battlefield has always been a challenge. Durable, sterile, plastic surgical instruments can be printed on-site with additive manufacturing. Because these products are designed digitally, they can be customized to the liking of each combat surgeon.

    Job opportunities exist and will continue to grow as this field expands. A technical school in Ohio is training students in advanced manufacturing, including 3D printing. They are being paid $18/hour directly out of high school.

Future

Much discussion of additive manufacturing is about what will be. In fact, as we discussed application areas such as automotive, we necessarily mentioned things that are coming in the future. The same is true with 3D printing in space. It’s not hard to see how 3D printing could play a large role in setting up a colony on Mars.

    Analysts anticipate that the U.S. will remain the largest market with 40% of global sales. Western Europe and China should be strong growth areas as well. If you have a keen interest in this technology and its development, you are encouraged to attend this year’s AM show, RAPID 2016, in Orlando, Fla., May 16-19.

Alliances

Alliances seem to be the key for future development. The National Additive Manufacturing Innovation Institute was founded in August of 2012, and they have been recently rebranded as America Makes. The group – a consortium involving Pennsylvania, Ohio and West Virginia – is focused on 3D printing and its research. It has received about $70 million in federal grants and private-sector funding, and more than 80 partners have joined as members. These partners include large corporations, small manufacturing companies and higher education from universities to community colleges.

    Lincoln Electric and a group of partners have joined with Case Western Reserve University to work on a $700,000 project funded by America Makes. It’s entitled “High Throughput Functional Material Deposition Using a Laser Hot Wire Process.” This is a second round of research, which seeks to generate structural parts with titanium alloys and functional surfaces with nickel-based alloys.

Materials and Part Size

We see materials as a key to growth in this field. Success with titanium would be one example of huge future opportunities with the military, aerospace, medical and other industries looking to utilize titanium’s light weight, strength and corrosion resistance. Much of the groundbreaking activity in 3D printing has utilized plastics, and moving from plastics into metals of all types is the next step.

    Along those lines, Sweden’s Exmet AB and Öhlins Racing AB have signed a license agreement to use 3D printing technology to produce amorphous alloy (metallic-glass) components. Amorphous steels (iron-based) have twice the strength and 10 times the elasticity of high-quality steel alloys. The strength is four times that of titanium alloys, and they are stainless. Exmet has manufactured net-shape components using metal-powder-bed AM with either laser- or electron-beam-based systems.

    Another development will be making larger parts. Machine-tool builder Cincinnati Inc. and the U.S. DOE’s Oak Ridge National Laboratory have recently initiated a partnership to build a bigger printer. Their goal is to develop a new AM machine to print polymer parts up to 10 times larger than what can be done with current technologies. They plan to speed up the process 200-500 times. With Cincinnati’s primary experience being metals, it’s not a stretch to say that larger metal AM parts will be the next development.

Customization

Flexibility and customization will be a development step in 3D printing technology. The technology lends itself to special-order parts and products. Can you see the next Amazon where people can go online to design the lamp they want, for instance? It could be made in the shape and color specified by the individual and made as a one-of-a-kind item.

    As printers become less and less expensive (HP is planning on releasing a 3D printer around the middle of 2015), individuals will be able to manufacture their own custom products in their basement or garage. Can you say entrepreneurial opportunity? If you are interested in a glimpse of where this is today, check out Thingiverse (www.thingiverse.com). What we can manufacture will soon be limited only by our imagination.

Ethics

You probably didn’t see that coming. When imagination is set loose, sometimes ethical questions arise. It’s doubtful this will be much of an issue in our industry, but bioprinting is coming along for the ride. Last year, scientists from Cornell University printed a human ear, and scientists in Scotland are developing the technique to print embryonic stem cells.

    Printing weapons is closer to our world than printing ears. A 3D-printed gun was created in 2012, and the blueprints were shared on the inventor’s website. They received 100,000 downloads before the U.S. State Department removed them. A video of the gun firing is still available.

Conclusion

Where is additive manufacturing going and how quickly? It’s not even clear to the experts when mass adoption will occur for AM, but the availability of lower-priced 3D printers will begin to make additive manufacturing (3D printing) a household word.

    What does that mean for your company? Does additive manufacturing make sense for your process? Could you grow your business by using AM? It may be time to consider whether your company needs a strategy for how to incorporate additive manufacturing into your production processes.

References available upon request