3-D Printing Promises to Change Manufacturing

Atoms, unlike bits, are hard to manipulate. Advances in how we rearrange them come slowly, but the payoff can be enormous.

Think new, never-before-seen products mass-produced from materials that once seemed exotic. Next to microchips, there is no more powerful unlocking technology than materials science.

This carbon-fiber component had been made on a 3D printer, a gadget more often associated with spitting out plastic novelties.

Marry those two technologies, and things get interesting. The all-electric BMW i3 has a carbon-fiber frame that extends its range by making it significantly lighter. Other possibilities include light but strong parts for drones and other aircraft, as well as replacing materials in many everyday objects—from furniture to machine tools—with carbon fiber.

“We give you the strength of metal for the cost of plastics,” says Greg Mark, chief executive of MarkForged Inc., a Cambridge, Mass., company founded in 2013 that sells a machine that 3-D prints carbon-fiber composites.

The printer costs $5,000 and is being used by at least one automotive manufacturer to make parts for the machines that make cars, according to Mr. Mark. The company won’t say which, but Nissan Motor Co. is listed as a customer on MarkForged’s website. “We like to tell people we’re the parts behind the part,” says Mr. Mark.

Nissan didn’t respond to a request for comment.

Today, such parts are most often made by machinists using computerized mills to carve solid blocks of metal. (This also is, incidentally, how the body of Apple Inc.’s laptops is produced.)

A competing carbon-fiber 3D-printing technology is taking on a potentially bigger opportunity—the method for producing the overwhelming majority of plastic parts.

“Our long-term goal is to replace injection molding,” says Robert Swartz, founder and chief technical officer of Impossible Objects LLC, which recently unveiled a machine that can 3-D print composites with a huge variety of materials.

Chicago-based Impossible Objects’ process combines fabrics such as silk, polyester, Kevlar, cotton or carbon fiber with any 3-D printable plastic, including ones used for high-temperature applications.

Impossible Objects’ process differs from previous 3D-printing technologies. Instead of printing an object one layer atop the other, every layer of the object can be printed at once, in two dimensions, on a large sheet of fabric. The layers are then cut out and stacked one on top of the other, like a layer cake, and baked in an oven.

The machine operates on the same principles as an inkjet printer, spraying the plastic out of print heads as tiny droplets, at high speed. That means it eventually could be fast, says Mr. Swartz. The maturity of traditional 2-D printing, on which Mr. Swartz’s process is based, makes him think it could someday be relatively inexpensive.

Traditional manufacturing won’t go away—we still make glass in essentially the same way as the Romans, after all—but it may never be the same again.