Aluminum casthouses are being pushed to use more recycled metal without sacrificing melt quality, recovery rates or production efficiency. The pressure is especially acute for post-consumer aluminum, lightweight scrap and machining chips, which are difficult to introduce into conventional melting furnaces. Efficient feeding and submergence are therefore central to improving recycling performance.
The operational problem is not limited to scrap preparation. Casthouses must maintain consistent temperature and chemical composition throughout the molten bath to produce specification-compliant aluminum. Circulation and stirring equipment must support heat transfer and metal movement while limiting process interruptions and excessive metal loss. Conventional mechanical pumps, although widely used, depend on immersed rotating components that can deteriorate through exposure to molten aluminum, dross accumulation and contact with refractory debris.
A magnetic route to molten-metal movement
Zmag America, Ltd. is positioned in this specialized segment of casthouse technology. Its work builds on industrial magnets and magnetic circuits, including earlier commercialization of eddy-current separation for recovering non-ferrous metals from mixed streams. The company later expanded into molten-metal applications and developed its patented zPMC, or Zmag Permanent Magnetic Circuit, as the basis for equipment that stirs, circulates and submerges material in molten aluminum.
The central distinction is between permanent-magnet and conventional electromagnetic systems. Zmag's zPMC uses a permanent magnetic circuit to generate the field that moves the molten metal, rather than relying on a conventional electromagnetic stirring arrangement. The company describes the resulting movement as a virtual impeller, allowing circulation without conventional immersed mechanical impellers.
Adoption is not only a technical question. In an August 2025 interview with AL Circle, Eishin Takahashi, president of Zmag America, identified limited familiarity with the technology as a barrier in the United States. He observed that aluminum producers globally tend to be conservative and more comfortable with equipment and processes they already know. That comment frames the commercial challenge facing any unfamiliar casthouse system: performance must be demonstrated in furnaces where downtime and metal quality carry high costs.
MagStir: non-contact furnace stirring
MagStir is Zmag's non-contact stirring system for aluminum melting and holding furnaces. It uses the permanent magnetic circuit to create movement in the molten bath and support homogenization of temperature and alloy composition. Zmag offers configurations for furnaces with capacities from 15 to 200 metric tons. Because the system does not require an immersed mechanical stirring component, it is presented as an alternative for casthouses seeking better melt circulation without adding moving parts to the molten-metal environment.
The application record 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. A MagStir unit was also fitted to a casthouse furnace at the Rio Tinto-operated Boyne Smelters in Queensland, Australia, in 2019. Those are reported installations and case-study findings, not a guarantee of performance across all furnace types or practices.
MagPump: circulation without an impeller
MagPump extends the magnetic approach from stirring to molten-metal pumping and circulation. The system is designed to fit a standard pump well without furnace modification. Unlike conventional mechanical pumps, it has no physical impeller and is marketed as a nearly hands-free alternative with no consumable parts and minimal downtime.
Its application was examined at the TANDEM Division of U.S.-based secondary aluminum producer TST Inc. in Fontana, California. During a seven-week trial, MagPump replaced an existing mechanical pump in a furnace used for aluminum production. The findings described smooth operation and reduced disturbance to the molten-metal surface. TST plant management also reported that the system avoided the splashing experienced with conventional pumping arrangements as the furnace metal level fell during draining.
The technology was presented at the TMS 2023 Annual Meeting and Exhibition, where its use in side-well, multi-chamber furnaces was discussed. The presentation highlighted potential applications beyond primary metal circulation, including gas injection and scrap submergence. The reported trial results are operational evidence from specific installations, not a general performance guarantee.
Typhoon: submerging difficult scrap
Zmag's Typhoon system focuses on scrap submergence and chip melting. It is designed to introduce lightweight aluminum scrap and machining chips beneath 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 application. Neuman incorporated a Typhoon chip-submergence system into a furnace modernization project intended to expand its ability to process low-density post-consumer scrap. The targeted material included lightweight fractions with a bulk density of approximately 375 kg/m³, a feedstock that had challenged conventional furnace charging and melting.
According to the published technical account, operating results exceeded the initial expectations. 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, the Typhoon system processed almost twice the planned scrap quantity within the expected time without disrupting normal furnace operations. The company 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 published account. Its vortex intensity can be adjusted to suit operating requirements, allowing it to maintain molten-metal movement even when scrap or alloying material is not being charged.
A competitive field with different technical routes
The market includes several established suppliers, though not all offerings are direct equivalents to Zmag's permanent-magnet approach. ABB supplies its AL-EMS electromagnetic stirring system for aluminum melting, holding and alloying furnaces. Its technology has a substantial global installation base, with the company reporting 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, also operates in furnace stirring. Its portfolio includes 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 occupies an adjacent position in industrial automation 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.
Adoption will likely depend on furnace fit, operating evidence and willingness to move away from familiar mechanical equipment. As producers use more challenging recycled feedstock, managing molten-metal movement without conventional immersed components could become more relevant. Zmag's cases show where the company is testing that proposition; performance claims remain tied to specific furnaces, feedstocks and operating targets.