Aluminum casthouses are being pushed to raise recycled content without giving up melt quality, metal recovery or throughput. Lightweight post-consumer scrap, machining chips and other low-density fractions are difficult to charge into conventional melting furnaces, so feeding and submerging them efficiently has become central to recycling performance. The same operations must hold temperature and chemistry steady across the bath, which puts pressure on circulation and stirring equipment. Conventional mechanical pumps meet that need with immersed rotating parts that degrade in molten aluminum, dross and refractory debris.
Zmag America, Ltd. works in that niche, building magnetic systems for molten-metal circulation, furnace stirring and scrap recovery. Its technology base is the industrial use of magnets and magnetic circuits; the company traces its history to magnetic engineering and the commercialization of eddy-current separation for recovering non-ferrous metals from mixed streams, and later moved into molten-metal applications. Its patented zPMC (Zmag Permanent Magnetic Circuit) underpins equipment that stirs, circulates and submerges material in molten aluminum.
Permanent magnets rather than electromagnets
The company's distinction from conventional electromagnetic stirring lies in the field source. Instead of an electromagnetic stirring arrangement, zPMC uses a permanent magnetic circuit to generate the field that moves the molten metal. Zmag describes the resulting movement as a virtual impeller, because circulation is produced without immersed mechanical impellers. The practical value of that non-contact principle in a given casthouse depends on the furnace and its duty cycle, but it removes the immersed rotating component from the molten-metal environment.
MagStir for furnace homogenization
MagStir is a non-contact stirring system for melting and holding furnaces, using the permanent magnetic circuit to move the bath and homogenize temperature and alloy composition. Zmag offers configurations for furnaces from 15 to 200 metric tons, and the absence of an immersed stirring element is presented as a way to add circulation without extra moving parts in the melt.
The installation record extends beyond the United States. New Zealand Aluminium Smelters fitted the technology in a casting furnace and later extended it to further furnaces; a technical case study published in 2017 examined those installations and reported improved temperature control during furnace preparation. A MagStir unit was also installed at Rio Tinto-operated Boyne Smelters in Queensland, Australia, in 2019.
MagPump as a circulation alternative
MagPump applies the same approach to pumping and circulation. It is designed to fit a standard pump well without furnace modification, uses no physical impeller, and is marketed as a nearly hands-free option with no consumable parts and minimal downtime.
At the TANDEM Division of US secondary producer TST Inc. in Fontana, California, a seven-week trial replaced an existing mechanical pump in a production furnace. The reported findings describe smooth operation and less disturbance of the molten-metal surface; plant management also said the system avoided the splashing seen with conventional pumping as the metal level dropped 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 alongside potential duties such as gas injection and scrap submergence.
Typhoon targets low-density scrap
Typhoon addresses scrap submergence and chip melting, drawing lightweight scrap and machining chips below the bath surface instead of letting them float. Its magnetic circuit generates a vortex-like movement that pulls material into the melt to support heat exchange and recovery.
Neuman Aluminium's Marktl facility in Austria installed a Typhoon chip-submergence system as part of a furnace modernization intended to widen its range of low-density post-consumer scrap; the targeted fractions had a bulk density of about 375 kg/m³ and had been difficult to charge and melt conventionally. According to the published technical account, Neuman set a target of one metric ton per hour while continuing to melt solid charge in the same furnace, and the system processed almost twice the planned scrap quantity in the expected time without disrupting normal operation, with low operator involvement and no reported negative effect 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, with adjustable vortex intensity that can keep the bath moving when no scrap is being charged.
A crowded supplier field
Furnace stirring, molten-metal circulation and scrap submergence have several established suppliers, though not all offer direct equivalents to permanent-magnet equipment. ABB supplies its AL-EMS electromagnetic stirring system for melting, holding and alloying furnaces and reports more than 430 installations; in April 2026 it announced a further order from Arconic for a fifth stirrer at a Hungarian casthouse. Presezzi Extrusion Group, through its Melting Technology division, offers the L.E.C. (Low Energy Consumption) Stirrer for melting and holding furnaces along with remelting and casthouse equipment. Pyrotek covers electromagnetic pump systems and its LOTUSS (Low Turbulence Scrap Submergence) technology, which uses a circulation pump and refractory well to submerge light scrap, and its UK operations include EMP Technologies Ltd. Rockwell Automation sits in adjacent industrial automation rather than permanent-magnet stirring, with furnace and ladle-shop control work including a modernization project for Mozal Aluminium.
Adoption is also a matter of familiarity. In an August 2025 interview with AL Circle, Zmag America president Eishin Takahashi named limited familiarity with the technology as a barrier in the United States, saying that "Globally, aluminum producers tend to be conservative and feel more comfortable with equipment and processes they are already familiar with." As casthouses take on harder recycled feedstock, the option of moving molten metal without immersed mechanical parts is likely to stay on the evaluation list.