Massachusetts-based Desktop Metal aims to sell a more affordable 3D metal printing system that can be used for prototyping and mass production.

BMW's i Ventures division has invested in Desktop Metal, a Massachusetts-based company that specializes in 3D metal printing.

The startup aims to "bring metal 3D printing within reach of all design and manufacturing teams." Achieving the goal will presumably require a more affordable machine capable of producing complex mass-produced parts at costs competitive with traditional manufacturing methods.

The 3D printing industry has experienced significant growth in recent years, but most of the attention as focused on small rapid-prototyping machines that allow businesses or hobbyists to create items from plastic extrusions.

Some industries have already been using additive manufacturing to produce metal parts for decades. High costs have limited the technology to expensive low-volume components, however, such as the titanium exhaust outlet on a Koenigsegg One:1, parts for General Electric turbines, or engine chambers and valve bodies for SpaceX rocket engines.

"Compared with a traditionally cast part, a printed valve body has superior strength, ductility, and fracture resistance, with a lower variability in materials properties," SpaceX wrote in a 2014 announcement. "The (main oxidizer valve) body was printed in less than two days, compared with a typical castings cycle measured in months."

BMW plans to work with Desktop Metal to explore potential automotive applications for 3D printing. With backing from Lowes, Google Ventures and other venture capital firms, the startup hopes to launch its first product later this year.