- 04/08/2024
- Report
- Lightweight trend
WAAM vs. Die-Casting in the Automotive Industry?
Wire Arc Additive Manufacturing (WAAM) allows for lighter and stiffer components compared to traditional die-casting methods. This conclusion is reached by an automaker that compared the processes in trials using a strut brace as an example.


In Wire Arc Additive Manufacturing (WAAM), a wire, such as aluminum, is melted by an arc. A robot, controlled by software, lays down many weld seams on top of each other until the component is completed. Since the "pressure" of layer-by-layer deposition does not require consideration of demolding from a tool, hollow structures with an optimal ratio of stiffness to weight are possible.
As a result, the components can be lighter and stiffer than comparable parts currently produced in series, for example, by die-casting. Moreover, they can be produced more sustainably due to lower energy consumption and less material waste.
As a result, the components can be lighter and stiffer than comparable parts currently produced in series, for example, by die-casting. Moreover, they can be produced more sustainably due to lower energy consumption and less material waste.

"Already in this early phase of technology enablement, it is clear that the WAAM process can lead to lower emissions in the production process. The components can be produced more efficiently due to their lower weight, favorable material usage rate, and the ability to use green power," says Jens Ertel, head of BMW Additive Manufacturing. The next development step towards series maturity is the testing of components in the vehicle.
Due to the weld seams in the WAAM process, the surfaces of the components are not smooth but slightly wavy and must be finished in crucial areas. However, WAAM components can also be used without surface post-treatment for high, including cyclic, loads. To ensure durability directly from production, process parameters are crucial: The combination of welding process and robot path planning must be well-coordinated.
Due to the weld seams in the WAAM process, the surfaces of the components are not smooth but slightly wavy and must be finished in crucial areas. However, WAAM components can also be used without surface post-treatment for high, including cyclic, loads. To ensure durability directly from production, process parameters are crucial: The combination of welding process and robot path planning must be well-coordinated.
Manufacturing processes can complement each other
Various additive manufacturing processes do not necessarily compete with each other but should be seen as complementary. For high detail resolution, laser beam melting will continue to offer advantages over the WAAM process. In terms of the possible size of the component and the deposition rate, Wire Arc Additive Manufacturing seems superior, concludes the manufacturer.In perspective, the use of components in series vehicles of the BMW Group is envisaged. It is conceivable to produce individual parts with this process directly on the assembly line and manufacture different parts through software changes alone, without new tools. Additionally, sustainability can be further increased by using more recycled metals.