Munich. At the Additive Manufacturing Campus in Oberschleißheim, the BMW Group has a “live wire” to an modern, additive manufacturing course of for metallic automobile elements and instruments. In wire arc additive manufacturing (WAAM), a wire fabricated from aluminium or related is melted utilizing an arc. Then a software-controlled robotic locations numerous welding seams on high of one another with precision, till the entire element is completed. Because the strain signifies that layer by layer there isn’t any want to concentrate to demouldability, hole buildings with an optimum ratio between rigidity and weight are doable. This signifies that the elements might be lighter and extra inflexible than comparable die-cast components at present manufactured in sequence manufacturing. They will also be produced extra sustainably due to decrease vitality necessities and fewer materials waste. In the longer term, the plan is to make use of elements manufactured utilizing the WAAM course of in BMW Group manufacturing autos.
The WAAM course of is especially appropriate for big elements
The giant width and peak of a single welding seam signifies that elements might be produced extraordinarily shortly utilizing WAAM. In distinction to laser beam melting, which is already utilized in prototype and small sequence manufacturing on the BMW Group, WAAM is especially appropriate for bigger elements. The typical wall thicknesses are nicely suited to elements within the physique, drive, and chassis areas. However, instruments and gadgets will also be manufactured utilizing this high-tech course of, which can be used within the aviation business.
Development on the Additive Manufacturing Campus
The BMW Group is trialling this course of on the Additive Manufacturing Campus in Oberschleißheim, the place they’ve pooled manufacturing, analysis, and coaching on this space below one roof. With greater than 30 years’ expertise, the corporate is a pioneer within the space of additive manufacturing, generally generally known as 3D printing. BMW Group staff have been focussing on the WAAM course of, also called build-up welding, since 2015. A WAAM cell for the manufacturing of take a look at elements has been in use there since 2021. One of those instance functions is a suspension strut help, which, in intensive testing on the take a look at bench, is being in contrast with the sequence manufacturing element constituted of aluminium strain die-casting. “In this early stage it is already clear that the WAAM process can result in lower emissions in the production process. The lower weight of the components, their advantageous material usage ratio, and the option to use renewable energy means that the components can be produced more efficiently,” stated Jens Ertel, Head of BMW Additive Manufacturing. The subsequent stage of growth on the street to sequence manufacturing is testing elements within the automobile, which can begin within the foreseeable future.
The wider welding seams within the WAAM course of imply that the surfaces of the elements will not be clean, however barely rippled and have to be completed in important areas. However, BMW Group engineers had been in a position to reveal that WAAM elements can be utilized for top hundreds, together with cyclical hundreds, even with out post-treatment of the floor. Optimised course of parameters are essential for guaranteeing sturdiness instantly from manufacturing, so the mixture of welding course of and robotic path planning have to be coordinated optimally.
Configuration with generative design and algorithms
To make optimum use of the elements produced within the WAAM course of, the mixture of the manufacturing course of and a common new element design is paramount. To this finish, the BMW Group continues to speed up using generative design. Here, the pc makes use of algorithms to design optimised elements primarily based on the particular necessities. These algorithms are developed in shut collaboration with interdisciplinary groups and are partly impressed by evolutionary processes in nature. As with bionic buildings, step one is to make use of solely the fabric that’s really required for the topology of the element, and through fine-tuning within the second step, the element is strengthened solely the place mandatory. This in the end ends in lighter and extra inflexible elements in addition to higher effectivity and improved automobile dynamics.
“It’s impressive to see how WAAM technology has developed from research to become a flexible tool for not only test components but also series production components. The use of generative design methods enables us to make full use of design freedom and thus the potential of the technology. That was unthinkable just a few years ago,” stated Karol Virsik, Head of BMW Group Vehicle Research.
Production processes can complement one another
Different additive manufacturing processes will not be essentially in competitors with one another, reasonably they need to be seen as complementary. For instance, laser beam melting will proceed to be extra advantageous than the WAAM course of in relation to the best stage of element decision. In phrases of the doable dimension of the element and the deposition charge, nevertheless, wire arc additive manufacturing is superior. The BMW Group is initially planning centralised WAAM manufacturing of elements in Oberschleißheim, sooner or later, manufacturing at different places and using the expertise by suppliers can be doable. Further, it could even be conceivable to supply particular person elements instantly on the meeting line utilizing this course of and to fabricate completely different components with out new instruments, just by altering the software program. Sustainability will also be additional improved by rising using recycled metals.