Additive @ Ford

No stranger to the technology.
“We at Ford have been using additive manufacturing for over 25 years,” Ellen Lee, Team Leader, Additive Manufacturing Research, Ford Motor Co. says.

Admittedly, much of the early work was done on the classic rapid prototyping application, the creation of models. But subsequently, the applications have expanded in scope, as has the array of equipment that they have on hand to produce models—and parts.

“We do have a considerable array of commercial- and professional-grade equipment,” Lee says. They have selective laser sintering (SLS), stereolitho-graphy (SLA), fused deposition modeling (FDM), and direct-metal power printing.

Of the last, Lee says that most of those metal printers are in Europe, although they are starting to use the technology in North America.

“We also have some binder jet printing of sand where we have produced sand testing molds to make prototypes.”

What are they making?
“Most of the prototypes are plastics. Some are printed metal. Some are cast-ings made with a printed sand mold.

“We do a lot of models for new pro-grams and concept vehicles. But there are a large number of parts built that are functional and go to our racing pro-grams, where we need just one or two.

“We print a lot of air intake manifolds that can be put onto vehicles. It’s for testing, but they’re still quite functional. They can be put on dynamometers for 100,000 miles or so. They’re quite durable.”

Why do they do it?
Pretty much the usual reason.

“There are a lot of designs that we need to look at. To cut an injection mold takes quite a lot of time and is costly,” Lee says.

What are they doing to advance the tech?
“This year we created a research program in additive manufacturing.”

Through this, Lee and her colleagues are “seeing a lot of new technologies that will have a great impact on manufacturing for automotive.”

“For automotive.”
There’s the key phrase.

Sure, everyone knows about the use of additive for printing products like turbine blades for aerospace and knees for medical. But in these (and related) instances, the volumes are much, much lower than in automotive.

Lee says that one of the inhibitors to additive manufacturing is the cycle time of the process versus the cycle time for an existing process, like injection molding. “Today, looking at the technologies available right now, it is really tough for high-volume, mass-produced parts.”

But she notes that in their research program they’re looking at some new and emerging technologies that may address the issue of speed. (Not surprisingly, Lee doesn’t share what these technologies are.)

Another inhibitor she cites—“a big one”—is materials.

“Unlike aerospace or medical applications,” Lee says, “automotive has quite a number of more material types of interest that we might consider or like to have. So it is important to expand the number of material options.”

So in the Ford additive program, they’re working with an array of interests—established materials companies, start-ups, government labs, and universities—to help develop more materials that would be appropriate for automotive application.

A royal problem

There is another materials-related con-cern that Lee expresses vis-à-vis the greater use of additive manufacturing.

“In automotive, we use a large number of plastic and composite materials, and price is king for us.”

But here’s the rub: generally, additive equipment manufacturers supply the materials that are used on their machines. Consequently, Lee explains, it doesn’t help the cost equation when there is a single source for materials, the manufacturer of the machine.

She says, however, that as there is growing interest among general manufacturers who use a number of materials and who like to have more than one supplier there is likely to be an understanding on the parts of equipment manufacturers who will recognize that they’re going to need to increase the number of available materials, which should help reduce the costs.

How to compete on something not direct cycle time
Lee observes: “An instrument panel is usually made out of a polyolefin, polypropylene, which is not a material that can be printed but injection molded in about a minute.”

So two issues: (1) a material is used for a part that isn’t printable; (2) the cycle time is a fraction of what printing would require.

How can this be overcome?
Lee answers, “I don’t think what we want to do is compete part by part with the same design.” She thinks that it is important that parts be designed not with injection molding or machining or stamping or other conventional processes in mind, but to be produced with additive.

“It may be that we totally change the design and geometry to get the function we need out of it but while we consolidate many parts together. We may have geometries that can’t be molded that reduce weight and integrate a lot of function.

“Then if you start comparing that with the cycle time or overall time to make that assembly of parts, you’ll be able to start competing. And if you improve the quality overall because of this new design, you don’t have to meet the short cycle time.”

Simply stated: A holistic view that takes into account what can be functionally realized through additive may make it more competitive when comparing that component with what is necessary to do in order to achieve the same with conventional processes.

A bright outlook
One of the big challenges in automotive is mass reduction. “If you look at what additive manufacturing is really good at, weight reduction might be something that you really zero in on.” She explains that it is possible to create geometries that minimize weight without affecting performance through additive, geometries that can’t be readily achieved otherwise because of process limitations.

“If we concentrate on those types of applications in the short term, then there is good potential to improve quality of product. Then, as cycle times and materials improve, we will have more applications.”

Lee says, “I really believe that the technology is going to advance very quickly in this field because there is so much interest in it and potential for things like customization or special geometries that are not physically possible with a mold. Those are two areas we are looking at to exploit.”

She adds, “Thinking about how quickly the technologies have been advancing in the last couple years, there will probably be things out in the market in five years we can’t imagine.”

Which is saying a lot, given the generation-long experience that Ford Motor has had with the technology. 

FCA US Prints an Axle Housing

While it is important to evaluate the flow of oil inside axles and pinion carriers during development, it presents a challenge. Ordinarily, windows are cut into the components. However, during testing on dynamometers, the oil becomes milky, so not a whole lot is seen through the window.

So the engineers at FCA US came up with a new approach, using additive manufacturing to print the structure with a clear material. They can run it on the dyno and still see what’s going on.

According to FCA US’s Tom Sorovetz, the structure, which measures approximately 14 x 10 x 12-in., was printed on a SLA-7000 machine from 3D Systems (3dsystems.com) using DSM SOMOS 11120 resin (dsm.com/products/somos/en_US/home.html). The part took some 12 hours to print, then about two hours of finishing to make the housing more clear.

To see what’s going on inside an axle, the engineers at FCA US printed a clear housing. The entire thing is put on a dynamometer so that oil flow throughout the structure can be examined.