Gigacasting is getting a Reality Check

Gigacasting was still one of the most visible technologies at China Diecasting 2026. Large structural castings were shown throughout the exhibition, but the conversation around it has changed. A few years ago, much of the excitement was about the large machines themselves. Who would install the next one? How large would it be? How many parts could be integrated into a single casting?

This year, the question was much more practical: How do we actually make money with these machines? That is why one of my main conclusions from Shanghai was that Gigacasting is getting a reality check.

The Investment Phase is Turning into an Efficiency Phase

China moved incredibly quickly into Gigacasting. Machines were installed, new parts were developed, and companies accumulated experience at a speed that was difficult to match elsewhere. But this also created a lot of installed capacity. In several conversations at the exhibition, utilization came up. One number mentioned to me off camera was an average utilization of only around 30 to 35 percent. This does not mean that every Gigacasting machine is underutilized. There are also foundries where ten machines are occupied and another two are being installed because the business is already there.

Still, it shows how the discussion has changed. During the growth phase, the focus was on installing capacity. Now that capacity has to generate a return. At some point, you cannot continue spending millions on increasingly large machines. You need to make money with the equipment already installed.

Production Efficiency becomes the Competitive Advantage

Michael Cinelli from Bühler described exactly this transition. A significant amount of Megacasting capacity has been installed during the last four or five years. Now, he says, it is about starting to earn money with it. Combine that with the OEM cost pressure being transferred through the supply chain. The manufacturers that succeed will therefore need high production efficiency, high yield, good part design and a reliable die-casting process.

That changes the Gigacasting race. Once several companies have installed similar equipment, simply owning an 8,000- or 10,000-ton machine is no longer enough. The competitive advantage moves into the process: how reliably the machine produces good castings, how much scrap is generated, and how well the installed capacity is utilized.

The Designs Are Becoming More Pragmatic

The early Gigacasting discussion focused heavily on maximum integration. The ambition was to replace as many stamped and welded components as possible with one enormous casting. 

At China Diecasting, many designs appeared more pragmatic. The castings were still large, but they increasingly looked like components designed specifically to be good castings rather than assemblies where every possible function had been integrated. From an assembly perspective, combining everything in one casting sounds attractive. From a casting perspective, it makes the process considerably more difficult. Maximum integration is therefore not automatically the optimum way forward.

Rheocasting Can Solve Several Problems

When efficiency and output of the casting process become the core of the business case, this is where Rheocasting becomes particularly interesting for Gigacasting. With the correct solid fraction and tool design, Rheocasting can fill the cavity laminarly and at lower metal velocities. For Gigacasting, this solves several of the problems that are becoming increasingly important.

First, it opens the process window. Instead of relying on very high velocities to fill several metres of flow length before the metal freezes, the semi-solid slurry maintains its ability to flow while allowing lower filling velocities. That gives the process more room between an incomplete fill and the aggressive conditions that increase tool wear and process instability.

Second, Rheocasting improves the properties of structural castings. Production data shows very narrow property distributions and uniform properties in different directions. For a Gigacasting, where elongation at the end of a long flow path is critical in a crash situation, this consistency becomes especially valuable.

That should also translate into a lower scrap risk. If mechanical properties and filling behaviour become more consistent, fewer castings should fall outside the required specifications. With a Gigacasting, avoiding one bad shot matters far more than with a small conventional casting because every rejected shot represents a large amount of aluminium, machine time, and a lost vehicle production slot.

And Rheocasting can also address one of the largest cost drivers: machine size. Because the process requires less gating and overflow area and avoids part of the pressure peaks created by turbulent metal hitting the die, the required locking force can be reduced significantly. In existing applications, machine-size reductions of around 20 to 30 percent have been achieved, with even larger reductions possible depending on the component.

For Gigacasting, that becomes particularly interesting, because moving an application from an 8,000-ton to a 6,000-ton machine represented around €9 of savings per casting before considering other total-cost-of-ownership effects such as longer tool life. If Gigacasting is entering an efficiency phase, those are exactly the kinds of improvements the industry now needs.

Gigacasting isn’t Failing, it’s Growing Up

The reality check does not mean that Gigacasting is coming to an end. Large structural castings were still everywhere in Shanghai. China has accumulated considerable experience, and new machines are still being purchased where sufficient volume exists. But buying the machine was only the first phase. Now companies have to keep those machines utilized, achieve high yield, maintain reliable mechanical properties, simplify designs where necessary, and produce castings at a cost that works under increasing OEM pressure.

That is also why technologies such as Rheocasting will become more relevant now than during the initial Gigacasting hype. The discussion is no longer simply about whether a two-metre casting can be produced. It is about whether we can open the process window, increase elongation, reduce scrap, lower the required machine size and ultimately improve the economics of every casting produced.

The next Gigacasting race will therefore not necessarily be won by the company with the largest machine. It will be won by the company that can turn that machine into the most stable, efficient and profitable production process.