September 1, 2012

3-D Printing and the New Industrial Revolution

A looming impact on the metals industries

 This 3-D printer, made by Airwolf 3D in Southern California, operates on constantly updated open-source software.

Car doors sliding whole from a futuristic computer printer? Not quite yet. The technology, for now, is nibbling at the edges of the higher value ends of the metals industries.

It's been around since the 1980s: a variety of competing manufacturing processes collectively known as 3-D printing, which allow a computer-run machine to create plastic parts by applying thin layer after thin layer of material, fabricating an object. Its more formal name is additive manufacturing, to distinguish it from subtractive manufacturing. That's the time-tested, cut-it-out-of-something process that's been around since the first wheel was fashioned out of a block of wood 5,000 years ago.

3-D printing was originally envisioned as a way to produce small, one-time prototypes without the time and money-consuming need to retool machinery as design bugs were being worked out. The process very much resembles the way an ink-jet printer lays down ink to create a printed page, except that the deposit laying cartridge repeatedly covers the same ground to build up material.

While 3-D printing quickly found uses making customized products such as fitted hearing aids and dentures, it wasn't thought to be an especially efficient way of producing large numbers of identical objects. But dramatic improvements in 3-D printers, and the software running them, is on the verge of turning that on its head. By one estimate, a quarter of 3-D printing spending goes toward finished products rather than prototypes, a percentage likely to only increase. Small wonder that The Economist, in an April special report, put 3-D printing at the center of what it called “the third industrial revolution.”

Metal Applications

And now 3-D printing is starting to ramp up production of objects made of metal. So far the items, for the most part, are modest in size and production runs. They include medical applications such as knee implants, and now small parts for engines, water pumps and jewelry.

But the trend raises significant questions: What kind of a threat does additive manufacturing pose to the metals service industry, and its estimated $200 billion in annual U.S. sales? If metal forms can be generated by a machine on demand by pushing a button and looking at a computer screen, who needs a middleman industry that mainly maintains inventory and provides a first-cut of metal that is then shipped to end-manufacturers? Do metals service centers have to adapt quickly or face a gradual diminution, or even extinction?

History teaches us that it is not wise to count out the potential disruptive impact of new technology upon a long-established industry. Just ask any newspaper publisher what the Internet-based Craigslist has done over the past decade to classified advertising revenues. Query Eastman Kodak—now in bankruptcy proceedings—about the impact of digital cameras upon its film business. Inquire of print mapmakers what GPS has done to their businesses.

Yet ask now about the implications for metals service, and the answer is often a shrug of the shoulders, a vague prediction or even less. A recent overview of the metals service industry, its economics and its future by MSG, a New York City-based business evaluation firm, doesn't mention the impact of additive manufacturing at all. An MSG representative said it simply didn't occur to the firm to take 3-D printing into account.

“I don't know [how metals services will be affected],” says Terry Wohlers, whose Fort Collins, Colorado-based consultancy Wohlers Associates tracks developments in 3-D printing. He is as big an enthusiast of 3-D printing as exists anywhere on the planet. But his decades of research looks more into the growth of 3-D printing and its applications rather than who or what that growth will hurt.

 The CandyFab 4000 3-D printer can use granulated sugar as the printing medium. Here, it is printing a coil sculpture.

Technical Barriers for Metals

David L. Bourell, a University of Texas professor of mechanical engineering and materials science and engineering, just co-authored a scholarly article about the history of additive manufacturing. He sees enough technical barriers—cost, size, the slow speed of the process—to protect traditional metals service. For now. “In 10 years, who knows what will happen?” he wonders.

Clearly, while 3-D has made some inroads into metal, it has a very long way to go. Gonzalo Martinez is director of strategic research at Autodesk, the San Francisco, California, computer-assisted design firm whose software is used to produce a huge amount of 3-D printer work output. Metal 3-D printing “is starting to make some noise out there,” he says. Yet Martinez figures that despite all the hoopla, metal accounts for only 0.1% of all 3-D printing. “There is no volume,” he declares, and he doesn't see that changing in the near future.

One big reason is the sheer amount of time it takes to make metal objects of any size using 3-D printing. It would take a 3-D printer 100 hours to crank out a metal door for an automobile, Martinez figures. And that's only one part of a car. An assembly

line capable of manufacturing vehicles would take hundreds of 3-D printers.

Also, 3-D printers capable of fabricating larger metal parts cost hundreds of thousands of dollars.

And they still can't produce metal items with a diameter much wider than 1 foot. For the time being, that rules out a lot of work, since construction and automobile manufacturing accounts for two-thirds of the metals services market.

The Economic Barriers

Technology aside, the bottom line seems to be that the economics haven't arrived yet for a manufacturing line of 3-D printing in metal, especially if the output is more than about 5,000 items. The old-fashioned way of cutting out shapes remains a lot cheaper for the clients of metals service centers.

 The first 3-D printed car, the Urbee, being driven in Birds Hill Park near Winnipeg, Manitoba, took 15 years to complete.

And big runs are where all the money is. Metals, as one recent scholarly paper said, “are the major workhorse of our society and will remain so in the future.” Still, a paper published this year in the International Journal of Advanced Manufacturing Technology concluded that “currently additive techniques can be economically convenient and competitive to traditional processes for small- to medium-batch production of metal parts.”

Nonetheless, there are a lot of big thoughts in additive manufacturing. In 2010 Kor Ecologic, a Canadian engineering firm, and Stratasys, a Minnesota maker of additive manufacturing machines, managed to produce a working copy of what was described as “the first ever [vehicle] to have its entire body, including its glass panel prototypes, 3-D printed with an additive manufacturing process.” The tiny two-passenger, three-wheel, extremely fuel-efficient electric hybrid was called the Urbee (for Urban Electric). One small drawback: The mostly plastic project took 15 years to complete. Vehicle No. 2 is currently in the works.

It was in 1986 that the first patent was granted for a 3-D printing technology, described as an “apparatus for production of three-dimensional objects by stereolithography.” For two decades the focus of attention in 3-D printing was on using polymers. It's only been in the last few years that 3-D printing in metal has drawn growing interest, even though the first patent in this area also dates back to the mid-1980s.

3-D processes use computer-aided design software to create what is called an STL file that controls the hardware capable of producing objects in three dimensions. On the metal side there are several competing technologies to produce the end product.

Among the most prominent, electron beam melting uses an electron beam gun to create melted layers from metallic powder in a vacuum chamber. This process can produce objects of very high strength. Direct metal laser sintering employs a laser to melt and fuse a metal powder. A great virtue of this somewhat less-complicated process is the ability to fashion objects using all kinds of metals: copper, low alloy steel, aluminum and tungsten.

Most of the major makers of metal 3-D printers are based in Europe, including EOS in Germany and Renishaw in the United Kingdom.

Tech Barriers Remain As Well

Another factor likely to keep metal 3-D printing at bay in metals services is the complexity of the technology. Relatively, polymer-based additive manufacturing is

just a lot simpler. As early as 2009, Popular Mechanics magazine ran an article by TV talk show host and noted car buff Jay Leno about how he used additive manufacturing technology—a $3,000 digital scanner and a $15,000 3-D printer—to make a plastic model of a replacement part for his hot-water-powered 1907 White Steamer automobile. The model was then used to make a mold to cast the part in metal.

It's gotten to the point where one maker of aftermarket equipment, Stratasys, is rolling out a $10,000 3-D printer—called “Mojo”—small enough to sit on a corner of a desktop and capable of producing end-use parts in short runs for industrial uses. A number of manufacturers now make 3-D printers priced at less than $2,000.

Metal 3-D printing, on the other hand, generally requires more heat to process either metal powder or wire, as well as other doo-dads like anchors and supports to handle the heavier weight of metal over plastic.

Writing last year, Ian D. Harris, director of the Ohio-based Additive Manufacturing Consortium, described some limitations in metal 3-D printing. “The number of commercially made parts is low because of the high-performance demands and associated costs for industry to qualify parts,” he acknowledged. “There are a limited number of technologies commercially available . for commercial scale manufacturing.

. Continued development to 'productionize' the machines for full manufacturing readiness and further understanding of the materials properties is essential.” However, Harris, whose group includes end-use manufacturers, additive manufacturing equipment makers and academics, said the trends, technological and economic, were headed in the right direction.

In May, then-U.S. Commerce Secretary John Bryson told the Steel Manufacturers Association that the first pilot project of a public-private manufacturing initiative the Obama administration is pushing, the National Network for Manufacturing Innovation, would focus on additive manufacturing. “This could eventually change the way we think about how we manufacture steel and other advanced materials,” he said. (Bryson resigned his post in June following a hit-and-run car accident in California, apparently caused by a seizure while he was at the wheel.)

What clearly could lift the profile of metal 3-D printing—and affect metals service—are creative efforts that aim to get around the size limitation. Modern Machine Shop magazine recently described several of them. One involved the use of ultrasonic welding (no extra heat needed) to combine additive manufacturing-fashioned pieces into an object that otherwise would be too large for a single 3-D printer.

Right now, the metals service industry is protected by its significant efficiency and cost advantages. But it is far from certain that this will continue. There is an awful lot of money waiting for whoever can do digitally to metals services what, say, Jeff Bezos and his Amazon.com have done to bookstores.

William P. Barrett is a veteran journalist for national publications. He can be reached at wmpb@aol.com.