Giga Stamping to Compete with Giga Casting
June 10, 2025Comments
Die-cast aluminum has replaced some stamped and welded assemblies in high-end low-volume cars for many years—shock towers are one example. The switch to aluminum, which saves weight but comes with additional cost, typically provides a positive cost/kg saved. One example: Audi replaced 10 stamped components with one casting (Fig. 1) in the A6 front shock tower.
When die casting presses larger than 6000-ton capacity (commonly known as giga presses) became available in 2020, very large castings started to replace a greater number of stamped parts. The first application of giga casting was automobile rear ends. The first giga-cast rear end consisted of two castings for the Tesla Model Y, in 2020. By 2021 the rear end had become a single casting.
While a conventional rear end consists of 70 to 85 stamped parts spot welded together (Fig. 2a), the giga-cast aluminum rear end on the Chinese Zeekr 009 vehicle, as an example (Fig. 2b), eliminates 800 to 850 spot welds.
The term “giga stamping,” coined recently by Gestamp, refers to hot stamping large laser-welded blanks (LWBs) or overlap-patched blanks (Fig. 3). Potential applications for giga stamping include door rings and double door rings, battery-tray components (upper and lower covers, and ring), rear frame, roof ring, dashboard and rocker reinforcement.
The first application of large hot-stamped components were door rings. Since 2013, several U.S. OEMs have used laser-welded or single-piece door-ring designs for inner and outer reinforcements. The first application was the 2014 Acura MDX (Fig. 4a). In 2023, the Tesla Cybertruck became the first vehicle to feature a double door ring (Fig. 4b). Part dimensions reach nearly 3 by 2 m.
ArcelorMittal has trademarked the term “Multi-Part-Integration” (MPI) for large hot stampings and has displayed MPI components on several concept cars (Fig. 5, #8). ArcelorMittal and Gestamp use grade PHS1000 steel in deformation areas and PHS2000 in the safety cage.
Another possible area of giga stamping is the roof ring (Fig. 5, #9). This design allows for large sunroofs and performs well in IIHS roof-crush simulations. Front-end designs differ between ArcelorMittal and Gestamp. ArcelorMittal uses two shells to create the front rails, made of PHS1000 and stops the deformation with PHS2000 (Fig. 5, #1 and #2). Gestamp employs five giga stampings, with soft zones to tailor the deformation of front rails (Fig. 6a). A similar design already has been in mass production in the Chinese battery-electric vehicle (BEV) Xiaomi SU7 (Fig. 6b). 
Lastly, battery protection is of utmost importance for BEVs. Many recent BEVs, including the Tesla Model Y and BYD Seal, do not have a floor panel. Instead, the battery’s upper cover serves as the floor. In the ArcelorMittal NBEV, the floor panel and battery are designed as large LWBs. The lower tub is designed from PHS1000 and PHS2000 (Fig. 5, #5). The upper cover of the battery, which doubles as the floor of the vehicle, consists of four sub-blanks, made of PHS1500 and PHS2000 (Fig. 5, #4). A single-piece floor reinforcement serves as seat crossmembers, as well as a joining point for front and rear rails (Fig. 5, #3).
