Gigacasting: The Next Big Idea in Automotive Manufacturing?

Austin Weber // Senior Editor // webera@bnpmedia.com

Large-scale aluminum die-casting offers numerous pros and cons.

Traditionally, automobiles contain hundreds of structural metal parts that people never see. Whether it’s full front or rear underbodies, shock-tower modules or floor structures, they act as the “skeleton” of cars and trucks. Multiple components are riveted and welded together to form a safe, reliable framework that is covered with body panels.

However, automakers such as Ford, General Motors, Honda, Hyundai, Rivian, Tesla, Toyota and Volvo are rethinking that process. They are investing in new technology that enables them to produce large castings.

Tier One suppliers, such as Aisin and Ryobi, are also bullish on gigacasting. The goal is to consolidate parts, reduce complexity and eliminate weight.

A Big Idea

Gigacasting—also referred to as hypercasting, megacasting and unicasting—uses high-pressure aluminum die-casting to produce very large, single-piece structural components. It appeals to automotive engineers who are struggling to address the unique lightweighting challenges posed by electric vehicles.

Several companies make gigacasting equipment, including Bühler, IDRA and LK Machinery.

“Megacasting is an evolutionary step in die-casting,” says Michael Cinelli, head of product management and marketing at Bühler Group. “It uses the same fundamental physics, but applied at a dramatically larger scale, and with higher structural and quality requirements.

“It leverages ultra-large die-casting machines that generate between 6,000 and 9,000 tons of locking force,” explains Cinelli. “Megacasting relies on optimized alloys, advanced thermal management and integrated process control.”

Bühler unveiled its first ultra-large press in 2020 as automakers around the world began demanding more efficient production processes to meet the requirements of next-generation vehicles. Since then, the company has sold more than 50 Carat series machines to a variety of OEMs and suppliers.

Designed specifically for gigacasting applications, the huge presses feature die locking forces up to 92,000 kilonewtons. For instance, the Carat 920 machine can inject more than 200 kilograms of liquid aluminum into a die within milliseconds.

“This approach simplifies manufacturing, reduces vehicle weight and improves structural performance,” claims Cinelli. “With fewer joining processes and less material waste, megacasting also supports more sustainable production. It is suitable for both traditional and electric vehicle architectures.”

“Gigacasting delivers meaningful structural and cost advantages,” claims Ling. “It can dramatically reduce part counts, welds and assembly operations, while improving dimensional accuracy. Fewer joints and more uniform load paths enhance stiffness and crash performance.

“For EV manufacturers, simplification means faster platform development, lower capital intensity and weight savings that translate directly into extended range,” says Ling. “The process also supports local manufacturing, as large castings are often produced adjacent to final assembly plants, cutting logistics costs and emissions.”

New Production Philosophy

In North America, Tesla has been the only high-volume adopter of large, high-pressure die-casting, using it on the Model 3, Model Y and Cybertruck.

“Ford and GM are moving in that direction and have sourced giga-press equipment, but remain in early deployment phases,” explains Ling. “European automakers are more cautious. Volvo is the clear front-runner, investing heavily in megacast rear floors for its next-generation EVs, while most German OEMs are still running pilots.

“Asian automakers, particularly in China, are advancing the fastest,” Ling points out. “BYD, Geely/Zeekr, Li, NIO and XPeng, among others, already use gigacast front or rear modules and battery housings in production, with some experimenting with casting nearly the entire underbody.”

Megacasting disrupts decades of a “we always do it this way” mindset in the auto industry.

“For legacy automakers, integrating gigacasting into existing plants remains a hurdle, requiring reconfiguration of body shops and balancing new investment with existing stamping capacity,” says Ling. “Beyond the press itself, gigacasting depends on a complete casting ecosystem. That includes large melting and holding furnaces, vacuum systems to control porosity and tight temperature management throughout the process.

“Heavy automation handles ladling, part extraction and trimming, along with localized heat treatment or quenching where needed,” explains Ling. “Quality assurance is equally critical. High-end X-ray or CT scanners, ultrasonic inspection, dimensional measurement cells and straightening systems are all required to monitor and correct defects or distortion in these massive structural parts.”

“Engineers can integrate multiple sheet metal stampings into one net-shape component,” says Bühler’s Cinelli. “Cast-in ribs, bosses and flanges replicate stiffness and joining features previously created by separate brackets and reinforcements. Overlapping panels, hem flanges and spot-weld seams can be eliminated by using continuous wall sections and local thickening.”

Functional features that previously needed add-on parts can be embedded, such as:

• Mounting points—cast threaded bosses or machined pads for suspension, seats, batteries, crash rails and power train mounts.
• Joining features—lap/plug-weld zones, adhesive channels and self-piercing rivet landings, reducing separate reinforcements.
• Cable and pipe management—cast clips, channels and through-holes for wiring harnesses, brake lines and coolant lines.
• NVH features—stiffening beads, rib lattices and tuned thickness transitions can be used instead of separate braces.

“A company with Ford’s scale can really influence the supply chain and business practices across our entire industry,” adds Sue Slaughter, purchasing director at Ford Motor Co. “It is so important that we not only think about how [we] can use our purchasing power to fuel our business needs, but also to advance sustainability.”

Because the automotive supply chain is extremely complex, the Guiding Principles contain expectations about business ethics, working conditions, human rights, health and safety, environmental leadership and supply chain due diligence for suppliers at all tiers. All suppliers are expected to uphold these standards and enforce them throughout their supply chain.

The Guiding Principles are based on fundamental elements of social, environmental and governance responsibility that are consistent with applicable laws and international standards created by organizations such as the United Nations.

Topics covered under the revised guidelines include the following:

        Business ethics, including counterfeit parts and data protection.

        Environmental issues, such as air quality, carbon neutrality, chemical management, circularity and water management.

        Health and safety issues, such as personal protective equipment and workspace.

        Human rights and working conditions, such as benefits, wages and working hours.

        Responsible supply chain management, such as ethical sourcing of raw materials.

The BMW Group has implemented several projects in its packaging logistics unit to help the environment and conserve resources. The goal of the initiative is to work closely with suppliers to reduce carbon emissions and adhere to the principles of a circular economy.

BMW’s European assembly plants are using more recycled material in their packaging. For newly awarded contracts, the proportion of recycled material in reusable packaging for logistics purposes will almost double this year from around 20 percent to over 35 percent.

Using alternative sustainable materials, reducing single-use packaging, introducing lightweight packaging in certain areas and reducing transport volumes will also help cut carbon emissions.

BMW is monitoring the impact of individual measures via a CO₂ calculator for packaging. The automaker’s overall aim is to reduce CO₂ emissions in the supply chain by 20 percent per vehicle compared to 2019.

“Our re:think, re:duce, re:use, re:cycle approach is being implemented consistently in packaging logistics,” says Michael Nikolaides, head of production network and logistics at BMW Group. “We’re using innovative strategies to consistently reduce the volume of resources we use, thus reducing our carbon footprint.

“We are also doing our part to get the BMW iFACTORY up and running, with a particular focus on the ‘green’ side of things…with an emphasis on flexibility and efficiency, sustainability and digitalization,” explains Nikolaides. “It provides an answer to the challenges involved in the transformation to e-mobility and [leverages] the latest technologies to create a production process that uses minimal resources.”

According to Nikolaides, BMW is using more recycled material, such as expanded polypropylene (EPP) packaging. “Our newly developed EPP packaging already contains 25 percent recycled material,” he points out. “EPP is used in special containers, as its shape can be adapted to the components being packaged, allowing them to be transported safely.

“Around 360,000 of these containers are needed each year,” claims Nikolaides. “Using 25 percent recycled material allows us to save almost 280 tons of CO₂ annually. There are plans to increase this proportion of recycled material even further, with the first pilot schemes with 100 percent recycled material currently underway. If these tests are successful, this configuration will become standard for new contracts from 2024.

“An additional 680 tons of carbon emissions savings can be made every year by using covers and so-called small load carriers with 50 percent recycled contents,” says Nikolaides. “As things stand, these measures are focused within the European markets due to the current waste management situation and available recycling infrastructure. But, we are working toward expanding to our locations in China, Mexico and the United States.”

BMW also plans to use folding large load carriers in place of traditional pallet cages made of steel. The plastic alternatives will be made from over 90 percent recycled material. They work in a similar way to the collapsible shopping crates that most people are familiar with.

When they’re empty, the carriers can be folded up, making them easier to transport. Nikolaides claims that using 15,000 of these new containers will reduce CO₂ by around 3,000 tons per year.

“When it comes to packaging, the sky’s the limit,” says Nikolaides. “We’re launching pilot projects using bio-based materials to replace oil-based substances such as polyethylene and polypropylene.

“We are also investigating whether and in what ways we can use materials from recycled household appliances in our packaging,” explains Nikolaides. “In the long term, our aim is to use alternatives to raw materials across the board.”