Aluminium-Magnesium Alloy Foundry Output Rises as China’s Auto Lightweighting Demand Grows

Al-Mg alloy foundry

Aluminium-magnesium alloy foundry output in China rose strongly in 2025 as the automotive sector increased demand for lightweight structural materials. Output climbed by 8.8% from a year earlier to 9.05mn t, making it the fastest-growing major foundry product category.

Aluminium-magnesium alloy foundry output outpaced grey cast iron, ductile iron and steel castings, according to the China Foundry Association. The increase reflects the growing role of aluminium and magnesium in vehicle weight reduction, emissions reduction and new energy vehicle design.

Aluminium-magnesium alloy foundry output has also expanded steadily over a longer period. Compared with 6.8mn t in 2020, production rose by 33.1% over five years, equal to a compound annual growth rate of 5.9%.

The figures show that China’s foundry sector is shifting toward lighter, higher-value materials. Automotive demand remains the main driver, especially as electric vehicle and hybrid platforms require more weight-efficient structures.

Automotive Lightweighting Drives Alloy Casting Growth

China’s automotive sector consumed 15.8mn t of foundry products in 2025, up 5% from a year earlier. The sector accounted for 30.2% of total foundry demand, making it the largest and most important end-use market.

Lightweighting is becoming more important because automakers need to improve energy efficiency, extend driving range and reduce lifecycle emissions. Aluminium-magnesium castings support those goals by replacing heavier components in selected structural and mechanical applications.

New energy vehicles are a major demand source. Electric vehicles and plug-in hybrids need lighter body structures to offset battery weight, while also supporting higher efficiency and better performance.

This trend benefits aluminium-magnesium alloy producers, die casters and foundries with automotive qualification. It also supports demand for higher-quality feedstock, tighter process control and more consistent alloy chemistry.

China’s total foundry output across all materials reached 52.3mn t in 2025, up 3.1% from a year earlier. That was the second-highest level since 2001, after 54.05mn t in 2021.

The overall foundry market is therefore growing, but the strongest momentum is in lightweight alloys. This shows how vehicle electrification and emissions policy are reshaping metal demand inside China’s manufacturing base.

Magnesium Feedstock Demand Strengthens With Foundry Expansion

Magnesium alloy feedstock consumption rose by 32% on the year to 215,000t in 2025. The increase was driven by stronger aluminium-magnesium alloy foundry output and broader use of lightweight casting materials.

This matters because magnesium is a smaller but strategically important metal. It is used in aluminium alloys, die casting and lightweight components, making it closely tied to automotive and transport applications.

Upstream magnesium metal output also increased. China produced 391,200t of magnesium metal in January-April, up 21.6% from a year earlier.

The rise in magnesium production suggests that upstream supply is responding to stronger downstream alloy demand. However, the sector remains exposed to energy costs, environmental controls and regional production concentration.

For aluminium and magnesium markets, China’s foundry data confirm a structural demand trend. Lightweight casting demand is no longer a niche story. It is becoming a core part of automotive materials strategy.

The next phase will depend on vehicle production growth, new energy vehicle penetration and the ability of foundries to meet stricter quality standards. As automakers push for lighter platforms, aluminium-magnesium alloys should remain one of the main beneficiaries.

The Metalnomist Commentary

China’s foundry data show that lightweighting is becoming a real metals demand driver, not just an automotive design concept. Aluminium-magnesium alloys are gaining because EVs and hybrids need lighter structures to offset battery weight and improve efficiency.