Ampower, a consultancy firm specializing in industrial additive manufacturing advice, has published a insights report on the application of powder bed fusion (PBF) based metal 3D printing in automotive.
The report considers Laser Beam Melting (LBM) methods, as provided by Concept Laser, EOS, Trumpf, Renishaw and SLM Solutions, and Electron Beam Melting (EBM), which is commercialized by Arcam.
As a test automotive application, both methods are used in the end to production of a tail pipe for a Porsche GT2 RS. The parts and analayzed for their comparative effectiveness at each stage of the process, (design, production, post processing etc.)
Working out the weaknesses
Tail pipes are typically made by joining two sheets of metal with a welding seam. When in use, this seam is the main point of weakness for the tail pipe, and can lead to numerous iterations before arriving at a final design.
3D printing can create a tail pipe in a single part, making it an ideal alternative fabrication method for the component. In redesigning the pipe for 3D printing, engineers can also optimize the structure of the pipe’s inner shell, and give customers the option of personally branding the piece. Rapid fabrication also means that numerous designs can be tried in shorter out amount of time.
As the most popular means of metal 3D printing, LBM is tested against EBM to discover the strengths and weaknesses of each process.
3D printing for serial production
Metal 3D printing, at a glance, presents many advantages – geometric freedom, reduction in parts per assembly, light-weighting etc.- over the traditional method of manufacturing. However, the main barrier to widespread adoption in automotive is the cost of serial production.
In Ampower’s study, PBF 3D printing for prototypes is calculated based on a Concept Laser M2 dual LBM machines and an Arcam Q20. Serial production is tested using the same Arcam Q20 and an SLM Solutions SLM500HL with 4 lasers.
The report concludes that, generally, EBM is the most cost-efficient of the two methods for prototyping.
A quad-laser LBM system, by comparison, is more effective in serial production, given this specific application.
The report states”…the EBM technology is significantly more expensive for this application. The reason lies in the low part volume due to the thin walled design. Here, the benefits of high build rate of EBM machines cannot be applied,”
“High utilization of a quad laser system results in a high effective build rate of the LBM machine technology.”
The benefits of additive manufacturing
If produced in quantities of more that 20 pieces per year, manufacturers can save around 50% on the typical cost of producing a tail pipe by switching to additive. Additionally, post processing and further qualification are noted as potential causes of high cost in additive.
Overall conclusions state that, “this study shows that manufacturing of parts with high requirements on mechanical properties and optical finishing is feasible.
“For these applications Additive Manufacturing offers great potential to reduce the lead time and enable new designs.”
In addition, “It turns out that the fast lead time of around 25 days is a game changing benefit of additively manufactured automotive parts such as the reviewed tail pipe blend compared to traditional tool-bound production.”
Detailed insight about each part of the production process side-by-side can be read in the full report, Additive Manufacturing of Automotive Components, which can be accessed for free via the company’s website.
Featured image shows areas of potential additive manufacturing application. Image via Ampower