Aluminum casthouses are being asked to use more post-consumer recycled aluminum without sacrificing melt quality, recovery rates or production efficiency. Lightweight scrap, machining chips and other low-density materials are harder to feed into conventional melting furnaces, and once in the bath they must be distributed and submerged effectively. Consistent temperature and chemical composition across the molten bath are also essential for specification-compliant metal. That combination puts pressure on circulation and stirring equipment to move heat and metal while limiting interruptions and excessive metal loss.
Conventional mechanical pumps are widely used, but their immersed rotating parts can deteriorate through contact with molten aluminum, dross accumulation and refractory debris. Zmag America, Ltd. is positioning a different approach: magnetic engineering systems for molten-metal circulation, furnace stirring and scrap recovery. Its patented zPMC, or Zmag Permanent Magnetic Circuit, uses a permanent magnetic circuit to generate the field that moves molten aluminum. The company describes the resulting movement as a virtual impeller, allowing circulation without conventional immersed mechanical impellers.
A permanent-magnet route to molten-metal movement
The distinction matters because Zmag is not relying on a conventional electromagnetic stirring arrangement. Its systems use permanent magnets to create the moving field. In an August 2025 interview with AL Circle, Eishin Takahashi, president of Zmag America, identified limited familiarity with the technology as one barrier to wider adoption in the United States. He observed that aluminum producers globally tend to be conservative and more comfortable with equipment and processes they already know.
Zmag's portfolio applies the same principle to three casthouse tasks: stirring, pumping and scrap submergence. The products do not replace every part of furnace operations, but they target different points where molten-metal movement affects homogeneity, handling and recycling performance.
MagStir focuses on furnace homogenization
MagStir is a non-contact stirring system for aluminum melting and holding furnaces. It uses the permanent magnetic circuit to generate movement in the molten bath and support homogenization of temperature and alloy composition. Zmag says the system is available in configurations for furnaces from 15 to 200 metric tons. Because it has no immersed mechanical stirring component, it offers casthouses a way to improve melt circulation without adding moving parts inside the molten-metal environment.
The application history extends beyond the United States. New Zealand Aluminium Smelters installed MagStir in a casting furnace and later extended its use to additional furnaces. A technical case study published in 2017 examined those installations and reported improvements in temperature control during furnace preparation. Rio Tinto-operated Boyne Smelters in Queensland, Australia, also fitted a MagStir unit to a casthouse furnace in 2019.
MagPump and Typhoon widen the application
MagPump extends the magnetic approach to molten-metal pumping and circulation. It is designed to fit into a standard pump well without furnace modification. Unlike conventional mechanical pumps, it does not use a physical impeller and is marketed as a nearly hands-free alternative with no consumable parts and minimal downtime.
At the TANDEM Division of US secondary aluminum producer TST Inc. in Fontana, California, MagPump replaced an existing mechanical pump during a seven-week trial. The reported findings described smooth operation and reduced disturbance to the molten-metal surface. TST plant management also reported that the system avoided the splashing seen with conventional pumping arrangements as furnace metal level fell during draining. The technology was later presented at the TMS 2023 Annual Meeting and Exhibition, where its use in side-well, multi-chamber furnaces was discussed, along with potential for gas injection and scrap submergence alongside primary metal circulation.
Typhoon addresses a different bottleneck: getting difficult scrap beneath the surface. The system is designed to introduce lightweight aluminum scrap and machining chips below the molten-metal surface rather than letting them remain at the top of the bath. Its magnetic circuit generates a vortex-like movement that draws material into the melt, supporting heat exchange and recovery during remelting.
A recent installation at Neuman Aluminium's Marktl facility in Austria illustrates the target. Neuman incorporated a Typhoon chip-submergence system into a furnace modernization project to expand its ability to process low-density post-consumer scrap. The material included lightweight fractions with a bulk density of approximately 375 kg/m³, which had been difficult for conventional furnace charging and melting.
The operating results exceeded the initial expectations, according to the published account. Neuman had set a target of processing one metric ton per hour while continuing to melt solid charge materials in the same furnace. During operation, Typhoon processed almost twice the planned scrap quantity within the expected time without disrupting normal furnace operations. Neuman also reported low operator involvement and no negative impact on melt or finished-product quality. The system operates at 5-15 kW, including its air-cooling blower, and can submerge up to five metric tons per hour of machining chips, according to the technical account. Its vortex intensity can be adjusted to suit operating requirements, including maintaining molten-metal movement when scrap or alloying material is not being charged.
What the cases show, and what they do not
The evidence is concentrated in specific installations and company or technical accounts. It indicates that permanent-magnet systems can perform stirring, pumping and submergence duties in selected furnaces, and that users have reported operational benefits. It does not establish a universal performance advantage across furnace types, scrap mixes or operating practices. Nor does the material provide comparative energy use, metal recovery or maintenance-cost figures across sites. For casthouses, the relevant questions remain site-specific: whether the magnetic unit fits the furnace layout, how it interacts with existing charge and drain practices, and whether the claimed reduction in immersed components translates into the expected maintenance profile.
A competitive field, not a single technology
Zmag is not alone in supplying equipment for aluminum furnace stirring, molten-metal circulation and scrap submergence. ABB supplies its AL-EMS electromagnetic stirring system for melting, holding and alloying furnaces and reports more than 430 installations. In April 2026, ABB announced a further order from Arconic for a fifth stirrer at its Hungarian casthouse, following earlier installations at the same facility.
Presezzi Extrusion Group, through its Melting Technology division and North American presence, offers the L.E.C. Low Energy Consumption Stirrer for melting and holding furnaces, alongside equipment for aluminum remelting and complete casthouse operations. Pyrotek has a broader casthouse equipment presence, including electromagnetic pump systems and its LOTUSS Low Turbulence Scrap Submergence technology. Its EMP systems use electromagnetic forces to circulate molten aluminum and support metal transfer and scrap charging, while LOTUSS uses a circulation pump and refractory well to submerge lightweight scrap. Pyrotek's UK operations include EMP Technologies Ltd., which is involved in the design, sale and installation of metal-melting and circulation systems incorporating electromagnetic pumps.
Rockwell Automation operates in an adjacent industrial automation segment rather than offering a like-for-like permanent-magnet stirring product. Its aluminum-sector work includes furnace and ladle-shop control systems, as shown by a modernization project for Mozal Aluminium's casthouse operations.
The competitive landscape suggests that casthouses will compare magnetic stirring with established electromagnetic, mechanical and refractory-based approaches rather than adopt a single category. Zmag's differentiation lies in the permanent-magnet circuit and the absence of immersed mechanical impellers in its core products. That distinction may become more relevant as producers incorporate more challenging recycled feedstock and look for ways to manage molten-metal movement without relying on conventional immersed components. Adoption, however, will still be shaped by familiarity, integration and demonstrated performance at individual plants.