To relieve all strains and restore EFINEA Alloy 50 (High Permeability 49®) to a soft condition suitable for drawing, spinning, forming, bending and similar operations, anneal for not more than one hour at 1450°/1600°F (788°/871°C).
High nickel, high permeability alloys readily absorb carbon, oxygen, sulfur, and other contaminants from combustion furnace gases. It is recommended that in-process annealing be done in a hydrogen or inert gas atmosphere.
Ferromagnetic Standard Hydrogen Annealing
Prior to annealing all oil, grease, lacquer and any contaminants must be removed from the alloy.
Separate individual parts by an inert insulating powder (aluminum oxide or magnesium) or surface insulation media during the hydrogen anneal process.
To achieve optimum magnetic and electrical properties including maximum softness, EFINEA Alloy 50 (High Permeability 49®) should be annealed in an oxygen-free, dry hydrogen atmosphere with a dew point below -40°F (-40°C) for two to four hours at 2150°F (1177°C).
Follow by a furnace cool rate of 100°/200°F (55°/110°C) per hour down to 800°F (427°C) and at any rate afterwards.
