Ferromagnetic steels are very important industrially for their numerous applications in the electric and electromagnetic sectors.

They are defined as magnetically soft steels, characterised by high magnetic permeability and used in the production of solenoids, relays and petrol / diesel injectors for automobiles.

These applications require that the steel be easily magnetised and demagnetised. Groups of stainless steels have been designed with ferritic structures and a specific analytical balance that guarantees improved resistance to corrosion and good magnetic properties.

Where there is the need for particular resistance to corrosion for a specific purpose or environment, when very high magnetic permeability values and equally low coercive force values are required, Iron Silicon alloys are the only solution, but one that requires careful analysis of appropriate surface protection methods because of the tendency of these alloys to rust easily.

Magival® is a range of ferritic stainless steels, with a high degree of machinability, designed for magnetic applications where there are requirements for:

  • High permeability
  • Low coercive force
  • High machinability


Carefully controlled chemical analysis and sophisticated working processes create a ferritic structure which is highly sensitive to variations in a magnetic field. This avoids the need for expensive heat treatment by the user after machining. Due to their extreme ease of magnetization and demagnetization, the Magival® grades can be used to advantage in the manufacture of:

  • Magnetic cores
  • Solenoid valves
  • Electromagnetic devices
  • Flow regulators
  • Injector components

Iron Silicon alloys are generally used in applications requiring higher electrical resistivity, higher permeability, lower coercive force and residual magnetism than provided by either carbon steels or soft magnetic stainless steels such as the Magival® series.

Valbruna grades of Iron Silicon Alloys are classified according to the silicon content in the chemical composition according to the standard classification of ASTM A867.

Each single grade has got its enhanced machinability option where required.

Iron Silicon alloys are normally supplied in the annealed condition since the best magnetic properties can be reached through a soft magnetic annealing carried out after part machining.

Iron Silicon alloys rust easily under ordinary atmospheric conditions and therefore a protective coating should be applied to the heat treated parts if exposed during their life cycle.

Due to their high magnetic properties, Iron Silicon Alloys are mainly used in the manufacture of relays, solenoids and injectors parts.