HERMIGA Gas Atomisers
Vacuum-inert gas atomisers with crucible capacities covering laboratory-scale (3kg) R&D/Pilot systems through to Production Plant (200kg) capable of daily tonnage quantities. Rapid heating, bottom pouring or tilt/pour induction furnaces to 1750degC are available throughout the HERMIGA range with resistance-heated tundish systems as lower cost alternatives.
All HERMIGA systems use PSI’s unique ‘close-coupled’ atomisation die/nozzle configuration for ultra fine median sizes, controlled particle size distributions and gas economy. Selectable process conditions control particle size according to application requirement, enabling production of spherical powders with particle sizes from sub-micron to greater than 250 microns.
A common problem with conventional atomisation systems has been variation of metal feed rates leading to a broad distribution of powder particle sizes. HERMIGA atomisers control over-pressure in the melt chamber enabling the atomisation die to operate most effectively in a non-aspirating mode. This minimises metal flow rate change due to a reduction of the metallostatic head pressure thereby stabilising gas metal ratios, which in turn narrows particle size distributions.
An understanding of the metallurgical requirements of metal melting, refining and atomisation processes enables powder production to the highest standards of cleanliness, morphology and microstructure. Similarly, dedicated vacuum-gas management systems provide the desired levels of low oxygen or required levels of passivating gas to enable the safe operation of the equipment even when atomising highly reactive metals.
Touch screen Human Machine Interfaces (HMI) enable system automation such that the atomisation process can be handled automatically from a single, user-friendly Control position. System operation is supervised by microprocessor based Programmable Logic Controllers which check for correct operator commands and provide safety interlocking in the event of alarm conditions arising.
The equipment is designed to international standards and is manufactured with a complete range of safety features as standard. Bursting discs, splash can, out-of-range alarms and an automatic system shutdown facility ensure that the safe operation of PSI atomisers is always paramount.