A hollow steel wire filled with pure magnesium granules and/or a magnesium alloy and possibly with other components such as FeSi, CaSi, cerium mixed metal for the production of spheroidal graphite cast iron or Compacted graphite iron.
The wire is uncoiled into the liquid iron inside the treatment ladle by a special drive with adjustable feed rate. It must be ensured that the wire dissolves at the bottom of the ladle (Figure 1), and the feed rate has to be selected accordingly.
Advantages of this Mg treatment method are the use of low quantities of materials, low temperature loss, possible automation with minimum personnel requirements, and environment friendly process conduct. In addition, it is also possible to combine the process with iron desulfurization by means of magnesium prior to magnesium treatment (filling wires with increased magnesium content, e.g. 25% Mg, 20% Ca, 40% Si).