Aluminium casthouses are being asked to raise their use of recycled metal without sacrificing melt quality, recovery rates or production efficiency, and that is turning attention to how molten metal is moved inside the furnace. Zmag America, Ltd. builds its business on that problem, developing magnetic engineering equipment for molten-metal circulation, furnace stirring and scrap recovery instead of the immersed mechanical parts conventional pumps depend on.
The pressure starts with feedstock. As producers take in more post-consumer aluminium, lightweight scrap, machining chips and other low-density materials make up a larger share of the charge, and these fractions are difficult to feed into conventional melting furnaces. Efficient scrap feeding and submergence therefore become central to recycling performance. The problem continues past charging: temperature and chemical composition must stay consistent across the bath to meet specification, so circulation and stirring equipment has to deliver heat transfer and metal movement while limiting interruptions and metal loss.
From eddy-current separation to molten metal
Zmag's technical base is the industrial application of magnets and magnetic circuits. The company traces its origins to magnetic engineering and the commercialisation of eddy-current separation, used to recover non-ferrous metals from mixed streams, before extending into molten-metal work; its patented zPMC (Zmag Permanent Magnetic Circuit) is the platform for equipment that stirs, circulates and submerges material in molten aluminium. The field that moves the metal comes from a permanent magnetic circuit rather than a conventional electromagnetic stirring arrangement, and the company describes the resulting movement as a virtual impeller because circulation is produced without immersed mechanical impellers. In an August 2025 interview with AL Circle, Zmag America president Eishin Takahashi named limited familiarity with the technology as a barrier to wider US adoption, noting that producers globally tend to be conservative and prefer equipment and processes they already know.
MagStir is a non-contact stirring system for melting and holding furnaces, using the permanent magnetic circuit to homogenise temperature and alloy composition; Zmag offers configurations for furnaces from 15 to 200 metric tons. New Zealand Aluminium Smelters installed it in a casting furnace and later extended it to further furnaces, and a 2017 case study reported improvements in temperature control during furnace preparation. A unit was fitted to a casthouse furnace at Rio Tinto-operated Boyne Smelters in Queensland, Australia, in 2019.
MagPump applies the approach to pumping and circulation, fitting a standard pump well without furnace modification and using no physical impeller; it 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. Reported findings included smooth operation and less disturbance of the molten-metal surface, and plant management said the system avoided the splashing seen with conventional pumping as the metal level dropped during draining. Side-well, multi-chamber furnace applications, plus potential uses in gas injection and scrap submergence, were presented at the TMS 2023 Annual Meeting and Exhibition.
Typhoon addresses scrap submergence and chip melting, drawing lightweight scrap and machining chips beneath the bath surface rather than leaving them floating; its magnetic circuit creates a vortex-like movement that pulls material into the melt to support heat exchange and recovery. At Neuman Aluminium's Marktl plant in Austria, the system was added during a furnace modernisation aimed at low-density post-consumer scrap, including fractions with a bulk density of about 375 kg/m³. Neuman targeted one metric ton per hour while continuing to melt solid charge in the same furnace, and the system processed almost twice the planned quantity within the expected time without disrupting normal operations, with low operator involvement and, the company reported, no negative effect on melt or finished-product quality. The published technical account states that Typhoon runs at 5–15 kW including its air-cooling blower, can submerge up to five metric tons per hour of machining chips, and allows vortex intensity to be adjusted so metal movement continues when scrap or alloying material is not being charged.
Competing equipment already in place
The field includes established suppliers whose products are not all direct equivalents. ABB's AL-EMS electromagnetic stirring system serves melting, holding and alloying furnaces with more than 430 installations, and in April 2026 the company announced a further Arconic order for a fifth stirrer at a Hungarian casthouse. Presezzi Extrusion Group's Melting Technology division offers the L.E.C. Low Energy Consumption Stirrer alongside remelting and casthouse equipment. Pyrotek supplies electromagnetic pump systems and its LOTUSS low-turbulence scrap submergence technology, which uses a circulation pump and refractory well; its UK operations include EMP Technologies Ltd. Rockwell Automation sits in adjacent industrial automation, supplying furnace and ladle-shop control systems such as those used in a Mozal Aluminium casthouse modernisation, rather than a like-for-like permanent-magnet stirrer.
Zmag's case rests on where casthouses go next. If producers keep taking on harder-to-process recycled feedstock, managing molten-metal movement without conventional immersed mechanical parts is likely to become more relevant, though adoption will still be weighed against familiarity with proven equipment.