Aluminum casthouses are under pressure to raise recycled-metal use without sacrificing melt quality, recovery or productivity. Lightweight post-consumer scrap, machining chips and other low-density feeds are difficult to charge into conventional furnaces, so efficient feeding and submergence have become more important. Consistent bath temperature and chemistry also depend on circulation and stirring that can transfer heat and move metal without excessive interruption or metal loss.
Zmag America is developing permanent-magnet systems for those tasks. The company’s background is in magnetic engineering and eddy-current separation for non-ferrous recovery, and it later moved into molten-metal applications. Its patented zPMC circuit is the basis for equipment that stirs, circulates and submerges material in molten aluminum. Zmag says the circuit produces a “virtual impeller” effect, generating movement without the immersed mechanical impellers used in conventional pumps.
MagStir targets furnace homogeneity
MagStir is a non-contact stirring system for melting and holding furnaces. It uses the permanent-magnet circuit to move the bath and homogenize temperature and alloy composition. Zmag offers configurations for furnaces from 15 to 200 metric tons. Because there is no immersed mechanical stirring component, the system is presented as a way to improve circulation without adding moving parts to the molten-metal environment.
New Zealand Aluminium Smelters installed MagStir in a casting furnace and later extended it to other furnaces. A 2017 case study reported better temperature control during furnace preparation. Rio Tinto’s Boyne Smelters in Queensland, Australia, fitted a MagStir unit to a casthouse furnace in 2019.
MagPump and Typhoon extend the approach
MagPump applies the same magnetic approach to pumping and circulation. It is designed to fit a standard pump well without furnace modification and has no physical impeller. Zmag markets it as a nearly hands-free option with no consumable parts and minimal downtime. At TST Inc.’s TANDEM division in Fontana, California, a seven-week trial replaced a mechanical pump. The trial findings described smooth operation, less disturbance of the metal surface and avoidance of the splashing seen with conventional pumping as furnace level fell during draining, a point also reported by TST plant management. The technology was also presented at TMS 2023 for side-well, multi-chamber furnaces, with potential uses including gas injection and scrap submergence.
Typhoon addresses scrap submergence and chip melting. It introduces lightweight scrap and machining chips below the bath surface, using a vortex-like magnetic movement to draw material into the melt and support heat exchange and recovery. At Neuman Aluminium’s Marktl plant in Austria, the unit was included in a furnace modernization aimed at low-density post-consumer scrap with a bulk density of about 375 kg/m³.
Neuman targeted one metric ton per hour while the furnace continued melting solid charge. According to the published technical account, the system processed almost twice the planned scrap quantity in the expected time without disrupting normal operations, with low operator involvement and no reported negative effect on melt or product quality. Typhoon operates at 5–15 kW including its air-cooling blower and can submerge up to five metric tons per hour of machining chips; vortex intensity is adjustable.
Competitive landscape
Zmag is not alone in supplying furnace stirring and circulation equipment. ABB’s AL-EMS electromagnetic stirring system has more than 430 installations, and in April 2026 ABB announced an Arconic order for a fifth stirrer at a Hungarian casthouse. Presezzi Extrusion Group offers its L.E.C. stirrer for melting and holding furnaces. Pyrotek supplies electromagnetic pumps and LOTUSS scrap-submergence technology, while Rockwell Automation works in adjacent furnace and ladle-shop controls. These offerings are not all direct equivalents to Zmag’s permanent-magnet design.
In an August 2025 interview, Zmag America President Eishin Takahashi said limited familiarity with the technology was a barrier in the United States and that aluminum producers globally tend to prefer equipment and processes they already know. As casthouses seek to use more challenging recycled feedstock, systems that move molten metal without conventional immersed components may attract more attention, but adoption will depend on demonstrated performance and site-specific operating conditions.