Though the aerospace industry has been a fertile sector for the exploration and adoption of metal additive manufacturing technologies, the automotive industry has remained somewhat more restrained. That is not to say that 3D printing isn’t being used in automotive production—it is being investigated by most if not all car manufacturers—though adoption has been limited due to a number of factors, including productivity and cost-per-part.
Recently, however, UK-based manufacturer Betatype demonstrated how AM can overcome these limitations within the automotive sector by manufacturing 384 qualified metal parts in a single build using laser powder bed fusion (LPBF). The project utilized Betatype optimization technology to cut part costs dramatically (from $40+ to $4) and reduce lead times (from 444 hours to just 34 hours).
In its case study, Betatype set out to challenge the commonly held belief that AM technologies—as they stand now—are incapable of meeting the high volume and low cost needs of certain consumer-facing industries, such as automotive. It says, rather, that the key to adopting AM in high-volume industries is to optimize process economics. In other words: to choose the most effective manufacturing process for each part produced.
By combining this knowledge with its own awareness of AM’s limitations and its optimization technology, Betatype says it is well positioned to help its customers create parts that are designed for AM and better performing than traditionally manufactured parts, but that are also economically viable.
In more practical terms, Betatype demonstrated how AM could be used for production manufacturing in the automotive industry by 3D printing a series of LED headlights. As the company explains, the project was born from the automotive industry’s recent switch to the use of LED headlights and its need to adapt to new thermal management challenges.
“Typically, these new components require comparatively large heatsinks which are often actively cooled,” writes the company. “Betatype recognized that the specific geometry for these metal parts made them ideal for producing with LPBF, which can consolidate multiple manufacturing processes into a single production method.”
To make the metal headlight part suitable for AM, Betatype first redesigned the part for printing using LPBF. In the redesign process, Betatype was able to design the part with built-in support features, which enabled multiple headlight parts to be stacked on top of one another in the build tray without the need for additional supports.
Though “full stacking” can often be considered a complicated feat (largely due to thermal stresses in the layer process), Betatype ensured the headlight parts were designed to reduce thermal stresses and could simply be snapped apart once printed. The novel stacking design proposed by Betatype ultimately enabled the company to “nest” a series of the parts together in order to optimize the printer’s build volume. As mentioned, a total of 384 parts were printed in a single print job thanks to this. The machine used to achieve this was the EOS M 280 system.
Better, cheaper, faster
In addition to designing the parts as stacked models, Betatype also utilized its expertise to optimize other aspect of the build process. As the company points out:
“Through specific control parameters, the exposure of the part in each layer to a single toolpath where the laser effectively melted the part was reduced significantly, with minimal delays in between. This, coupled with Betatype’s optimization algorithms and process IP, reduced the build time of each part from 1 hour to under 5 minutes per part. That’s 10x faster than using a standard build processor.”
In terms of cost, Betatype says it managed to bring cost-per-part down from over $40 to less than $4—a huge cost saving. It adds that using the EOS M280 or Renishaw’s RenAM500M—both single laser medium frame (SLMF) systems—it was able to bring build time from 444 hours to roughly 30 hours for the production of 384 headlight parts. With new multi-laser systems MLMF), however, it was even able to bring build time down to 19 hours.
“Using these high productivity systems, it was possible to realize a 19x gain in productivity over a year of production per system from 7055 parts to 135,168,” Betatype writes. “With an installation of 7 machines running this optimized process, volumes can approach 1 million parts per year—parts that are more functional and more cost-effective.”