Why Magnesium and Thixomolding are Exploding in China

Magnesium has been called the material of the future for decades. Its low density is nothing new. Neither is magnesium die-casting. And Thixomolding has also existed for many years.

Yet at China Diecasting 2026, magnesium suddenly felt like one of the hottest topics at the entire exhibition. Almost every machine manufacturer seemed to have a magnesium solution. I counted roughly 10 to 15 companies presenting new Thixomolding systems, many of which had entered the market within a surprisingly short time.

So the interesting question is not why magnesium is attractive. It is: Why is it happening now?

Everything Magnesium needs is Coming Together

China has good access to magnesium, applications are emerging, OEMs are actively looking at the material, and manufacturers are investing heavily in the required processing technology.

Under the current conditions we saw in China, magnesium was cheaper than aluminium. That creates a very different business case from markets where magnesium carries a significant price premium. Danny Wu from Bole described a similar development. Bole started pushing Thixomolding in 2019, when the patent expired, and the market was still difficult. Five or six years later, OEM interest has increased significantly. He sees lightweighting, cost-effectiveness, and government support coming together.

Michael Cinelli from Bühler also described magnesium as one of the topics currently driving the Chinese die-casting industry, with new applications and new feeding technologies appearing rapidly. The important point is that this is no longer just a discussion about density. An entire magnesium ecosystem is developing.

Thixomolding doesn´t automatically mean Semi-Solid Casting

When people hear thixomolding, they often automatically think about semi-solid magnesium. But that is not necessarily what every machine manufacturer is doing. Some systems use thixomolding mainly as a different way of handling and feeding magnesium. Instead of keeping a large bath of molten magnesium next to the machine, the material is melted inside the system and then injected.

For example, Haitian uses a process that injects magnesium that is 100% liquid. The advantage is therefore primarily the handling concept and the possibility of avoiding a conventional magnesium furnace and some of the associated cover-gas requirements. Other manufacturers are taking a different approach. Bole and Yizumi, for example, are working with a semi-solid fraction to gain the additional process advantages associated with semi-solid flow.

That distinction matters. Thixomolding describes a machine and feeding concept, but it does not automatically mean that the metal entering the die is semi-solid. The actual condition of the magnesium depends on how the individual process is operated.

Corrosion Remains an Important Discussion

One of the traditional arguments against magnesium is corrosion. And this came up from two very different perspectives during the exhibition. 

Colin from Regal Metal acknowledged that magnesium has disadvantages regarding corrosion. Their approach is partly on the alloy side. He explained that customers use magnesium alloys containing rare-earth additions to improve corrosion performance and reach corrosion behaviour comparable to ADC-12.

Danny Wu from Bole approached the same issue from the process side. For their semi-solid thixomolding process, he described lower porosity, improved strength, and improved corrosion resistance as advantages. He connected the corrosion performance particularly to a better surface because of the laminar filling during the semi-solid state.

That makes the corrosion discussion particularly interesting. The development is happening on several levels simultaneously: alloy development on one side and processing technology on the other. Simply saying that “magnesium corrodes” therefore misses much of what is currently happening in the industry.

Which Magnesium Process will Win?

Another thing that became clear in Shanghai is that there won’t be one solution for every application. Dedicated Thixomolding machines offer an interesting route into magnesium, but they also create a business challenge.

If you buy a dedicated machine, you need enough business to utilize it over its entire depreciation period, which is usually between 12 and 15 years. That is a significant commitment to a market that is still developing. That is why retrofit solutions for existing high-pressure die-casting machines are also appearing. For foundries, this could reduce the risk of entering the magnesium market while maintaining more flexibility in their installed machine base.

We are therefore seeing several approaches developing simultaneously: Conventional magnesium HPDC, fully liquid magnesium processed through thixomolding-style machines, true semi-solid thixomolding, and systems that allow existing HPDC equipment to process magnesium. The winning solution will likely depend heavily on the application.

This Time Magnesium has a Market Behind It

The big difference compared with earlier magnesium waves is that China is not simply talking about the potential anymore. Companies are building machines. OEMs are discussing applications. Alloy suppliers are developing materials. Tool suppliers are adapting to different process requirements.

And magnesium castings are appearing from small components all the way to battery-related parts and very large structural castings. Magnesium being lightweight is old news. What is new is that the resources, economics, applications, and production technologies are now moving in the same direction. That is why I do not expect the magnesium discussion in China to disappear again quickly.

The much more interesting question is which combination of alloy, process, and application will ultimately become the standard.