Silico Manganese (SiMn):


Mn alloys are mostly used in steelmaking and foundry activities.

Some 30 % of the manganese used today in steelmaking is still used for its properties as de-oxidant and a sulphide former. In this last case, it combines with sulphur avoiding the formation of iron sulphides, which sulphides are low melting point phases which become liquid at hot rolling temperatures and which, consequently, generate surface cracking.

The other 70 % of the manganese is used purely as an alloying element. Steels usually contain from 0,2 % to 2 % Mn depending on grades as Mn is the cheapest alloying element among those which enhance some key mechanical properties like strength and toughness. In the specific case of stainless steel, it can substitute expensive nickel in some austenitic grades called 200 series.

PreRish Tri is proudly producing Silico-manganese in two grades respectively as below

Natural Grade (SiMn):  PreRish Tri offers this as direct from our Mines to the buyer after crushing and grinding as according to the size instructions without adding or mixing anything.

Industrial Grade (SiMn):  PreRish Tri adds additional silicon in it. This process is to make SiMn a stronger deoxidizer and to improve mechanical properties of steel. In each Mn family carbon is controlled and is lowered when producing ‘‘refined’’ grades. Nitrogen, Boron, Titanium, Phosphorus are elements which can be controlled depending on requested specification.

Chemical Composition:

Typical grades are available. Other grades are on request. Valid sizes > 10 mm.

SiMn Low B65172.



Standard sizes: 20 – 80 mm, 10 – 50 mm, 3 – 25 mm

(+/- 5 to 10%)

Physical Specifications:  Density: 6.1 g/cm  Bulk density: approx. 3200 kg/m3

An angle of repose: 40°- 60°- depends on the material size

Melting range: 1060°c – 1285°c

Additional Info: It is the lumpy material with a silvery metallic surface.

Effects of the addition of silicomanganese to steel:

Both silicon and manganese have an important influence on the properties of steel, depending on the amount added and the combined effect with other alloying elements.

Silicon and manganese have a strong affinity for oxygen and will act as deoxidizers.

Deoxidation with SiMn results in cleaner steel, as the liquid manganese silicate formed coagulates and separates easier from the melt, compared to solid Sio2 formed during FeSi deoxidation.

Use of silicomanganese adds less carbon to steel compared to standard FeSi 75 plus HCFeMn.

Computational Fluid Dynamics calculations show that the yield of silicon from silico-manganese is higher than that of standard FeSi 75.