What Holds AM Back in Automotive Production? GM Additive Lead Describes Advances Needed

Can additive manufacturing deliver end-use part production for the automotive industry? It is already doing so in certain cases. For automaker GM, 3D printing has provided bridge production of an SUV component during the wait for mold tooling, and it is established for making end-use parts on Cadillac high-end models, including 115 end-use 3D printed parts on the Cadillac Celestiq. These are all low-quantity applications relative to what is typical of the auto industry. What advances will enable AM to go farther in automotive production? Stated another way, what holds AM back from being more of a production solution for automakers?

Paul Wolcott, lead engineer for additive manufacturing with GM, addressed this within a talk he gave at a recent ASTM International Additive Manufacturing Center of Excellence Workshop held at the Ohio State University. As part of that talk, he squarely listed the areas of advance he sees as important for enabling AM to better serve the auto industry as a production solution. To be clear, AM already plays a significant, growing role for automotive as a solution both for tooling and for other production hardware. But when it comes to directly making parts, Wolcott says the factors holding AM back from fuller and more dedicated production applications chiefly include these:

1. Cost

“If AM were cheaper, we would be doing more of it,” he says. Opportunities including assembly consolidation and freedom from the need for tooling are too great for automakers not to want to 3D print — but the part cost is frequently too high. And in the case of additive parts, Wolcott observes that cost is largely another way of seeing insufficient speed. “Currently the largest fraction of cost is machine throughput,” he says.

2. Material

Automotive production justifies materials tailored to this use. AM alloys that are specific to automotive applications will allow for properties and performance tuned to auto needs, reducing cost.

3. Takt time

This is a term not often associated with additive equipment, but it should be. Takt time is a vital measure of availability for any equipment that will deliver automotive production. Currently, machine turnover time in additive is too long, while uptime is too low. Improvement in these numbers is needed.

4. Finishing

3D printing implies the hope of being able to create a finished part in one operation. In reality, downstream work is generally required for AM components. If parts could come off the 3D printing machine suitable for the vehicle, Wolcott suggests this would go a long way toward making additive more attractive for production.

5. Supply base

Contract AM part producers often do not understand the auto industry Production Part Approval Process (PPAP). To address this, the choices available to an automaker like GM come down to “working with AM companies on automotive practices, or working with automotive suppliers on additive,” Wolcott says, adding, “We have done both.”