Magnesium Die-Casting Growth Constrained by China Supply Chain Dominance

International Magnesium Association (IMA)

Magnesium die-casting adoption remains limited despite cost advantages over aluminum, as supply chain risks and price volatility concerns overshadow material benefits. Primary magnesium prices have reached parity or dropped below aluminum prices over the past year, theoretically supporting substitution in automotive applications. However, magnesium die-casting expansion faces significant headwinds from China's 90% global market share and associated geopolitical supply risks that discourage automotive manufacturers from switching materials.

Material Advantages Drive Theoretical Demand for Magnesium Applications

Magnesium offers compelling technical advantages for automotive die-casting applications, particularly in electric vehicle lightweighting strategies. The metal's density equals approximately two-thirds that of aluminum, making it the lightest structural metal available for automotive components. Meanwhile, magnesium's lower melting point reduces energy consumption during casting processes, while higher thermal conductivity improves heat dissipation performance.

Automotive manufacturers currently use magnesium die-casting for engine blocks, transmission cases, steering wheels, and interior brackets where weight reduction delivers maximum benefit. These applications leverage magnesium's superior strength-to-weight ratio compared to aluminum alloys. However, aluminum maintains advantages in tensile strength for high-stress structural applications, limiting magnesium's potential market penetration.

Supply Chain Concentration Creates Investment Hesitation

China's overwhelming dominance of global magnesium production creates substantial supply security concerns for automotive manufacturers considering magnesium die-casting adoption. The country produces approximately 950,000 tonnes annually, representing 90% of global output, while other production remains limited to Brazil, Russia, Turkey, and Israel. As a result, no active primary magnesium production exists in Europe or the United States following US Magnesium's suspension in November 2024.

Recent price volatility reinforced automotive industry caution regarding magnesium die-casting investments, with the 2021 price spike prompting some manufacturers to halt new magnesium component development. CM Group managing director Alan Clark noted that die-casters remain concerned about magnesium price exposure without sufficient long-term supply guarantees. Therefore, automotive companies prioritize aluminum's supply security over magnesium's material advantages and cost benefits.

Environmental restrictions, semi-coke limitations, slag disposal procedures, VAT enforcement, capacity cuts, and tight dolomite supply have compounded Chinese production volatility. Brazilian magnesium producer Rima's CEO Ricardo Vicintin emphasized that geopolitical concerns explain widespread reluctance to increase magnesium usage. Consequently, magnesium die-casting growth remains constrained despite favorable economics and technical performance characteristics.

The Metalnomist Commentary

The magnesium die-casting market exemplifies how supply chain concentration can limit material adoption despite superior technical and economic attributes. While non-Chinese projects like Latrobe Magnesium, Verde Magnesium, and MFE Magnesium offer future diversification potential, none currently operate at commercial scale, leaving the automotive industry dependent on Chinese supply for the foreseeable future.