Ferro-alloy


Master alloy with iron as the base metal and one or more additional elements for use as an alloying agent (iron master alloy). The compositions of ferro-alloys are specified in DIN 17 560 to 17 569.

In addition to iron, ferro-alloys also contain a main alloying element which determines the name and possibly further elements. The raw materials or ores almost always require conditioning in order to increase the concentration of alloying elements and remove contaminants. As the elements of interest in the raw materials are all present as oxides, ferro-alloys are primarily produced by means of reduction metallurgy or refining methods. These methods are used to minimize the percentage of contaminants.

Forms used for delivery are mainly pigs, wafers, splatter or ferro-alloy briquets pressed into briquet form from granular ferro-alloys using a binder (e.g. cement). The following is an overview of the most important ferro-alloys:

Ferroaluminum
Iron-aluminum master alloy with varying aluminum contents from 8 to 10% Al, 14 to 16% Al, 20 to 23% Al, 35 to 40% Al or 45 to 50% Al.

Ferroboron
Iron-boronmaster alloy according to DIN 17 567, as:

  • FeB 16: 15 to 18% B, max. 4.0% Al, max. 1.0% Si, max. 0.10% C, max. 0.50% Mn.
  • FeB 18: 18 to 20% B, max. 2.0% Al, max. 2.0% Si, max. 0.10% C, max. 0.50% Mn.
  • FeB 12 C: 10 to 14% B, max. 0.50% Al, max. 4.0% Si, max. 2.0% C, max. 0.50% Mn.
  • FeB 17 C: 14 to 19% B, max. 0.50% Al, max. 4.0% Si, max. 2.0% C, max. 0.50% Mn.

Ferrochromium
Iron-chromium master alloy, standardized according to DIN 17 565, as:

  • Ferrochromium (low-C, with low carbon content), FeCr 70 with 65 to 75% Cr, max. 1.5% Si and max. 0.01–0.02–0.04–0.06–0.08–0.10–0.50% C.
  • Ferrochromium, nitrogen-bearing (low-C, with low carbon content), FeCr70NC 10 with 60 to 72% Cr, max. 1.5% Si, 2.5 to 4% N and max. 0.10% C.
  • Ferrochromium (medium-C, medium carbon content), FeCr70 with 65 to 75% Cr, max. 1.5% Si and 0.5 to 1.0% C or 1.0 to 1.5% C or 1.5 to 2.0% C or 2.0 to 4% C.
  • Ferrochromium (high-C, high carbon content), FeCr70 with 60 to 72% Cr, max. 1.5% Si and 4.0 to 6.0% C or 6.0 to 10.0% C.
  • Ferrochromium, Si-bearing (high carbon content), FeCr70C6Si with 60 to 72% Cr, 1.5 to 10% Si and 4.0 to 8.0% C.

“Low-C ferrochromium” is also called ferrochromium suraffiné. Similarly, “medium-C ferrochromium” is called ferrochromium affiné and “high-C ferrochromium” ferrochromium carburé.

Ferrochromium-silicon (silico-chromium)
Chromium-silicon-iron master alloy, standardized according to DIN 17 565, as:

  • FeCr40Si: 40 to 45% Cr, 40 to 35% Si, max. 0.05% C.
  • FeCr60Si: 55 to 65% Cr, 25 to 20% Si, max. 0.05% C.

Ferrocobalt
Ferro-alloy with approx. 75 to 78% Co, the rest being Fe.

Ferrocopper
Copper-iron master alloy with 10 or 20% Fe.

Ferromanganese
Manganese-iron master alloy, standardized according to DIN 17 564, as:

  • FeMn85C01: 80 to 92% Mn, 1.0 to 1.5% Si, 0.05 to 0.50% C, max. 0.25% P.
  • FeMn85C01P015: 80 to 92% Mn, 1.0 to 1.5% Si, max. 0.15% P, 0.05 to 0.50% C.
  • FeMn85NC01: 80 to 92% Mn, 1.0 to 1.5% Si, 2.0 to 2.5% N, max. 0.25% P, 0.05 to 0.50% C.
  • FeMn85NC01P015: 80 to 92% Mn, 1.0 to 1.5% Si, 2.0 to 2.5% N, max. 0.15% P, 0.05 to 0.50% C.
  • FeMn80C1: 75 to 85% Mn, 0.5 to 1.5% Si, max. 0.25% P, 0.51 to 2.0% C.
  • FeMn85NC1: 80 to 90% Mn, 0.5 to 1.5% Si, 1.0 to 2.0% N, max. 0.25% P, 0.5 to 2.0% C.
  • FeMn75C7: 75 to 80% Mn, 6.0 to 8.0% C, max. 1.5% Si, max. 0.35% P.
  • FeMn75C7P015: 75 to 80% Mn, 6.0 to 8.0% C, max. 1.5% Si, max. 0.15% P.

The four grades mentioned first have a low carbon content and are referred to as ferromanganese suraffiné. The next to grades have medium carbon contents and are summarized under the name ferromanganese affiné. The two last high-carbon grades belong to the group of ferromanganese carburé.

Ferromanganese-silicon
Manganese-silicon-iron master alloy (silico-manganese), standardized according to DIN 17 564, as:

  • FeMn65Si: 58 to 72% Mn, 23 to 35% Si, 0.1 to 0.5% C, max. 0.20% P.
  • FeMn70Si: 65 to 75% Mn, 15 to 25% Si, 0.5 to 2.0% C, max. 0.20% P.

Ferromolybdenum
Molybdenum-iron master alloy, standardized according to DIN 17 561, as:

  • FeMo70: 60 to 75% Mo, max. 1.0% Si, max. 0.10% C, max. 0.10% P, max. 0.10% S, max. 0.50% Cu.
  • FeMo62: 58 to 65% Mo, max. 2.0% Si, max. 0.5% C, max. 0.10% P, max. 0.10% S, max. 1.0% Cu.

Ferronickel
Iron-nickelmaster alloy, standardized in DIN EN 26501, as:

  • FeNi25: 20 to 30% Ni (+Co), max. 0.030% C, max. 0.10% Cr, max. 0.05% Si, max. 0.030% P, max. 0.040% S.
  • FeNi25C: 20 to 28% Ni (+Co), max. 2.0% C, max. 2.0% Cr, max. 4% Si, max. 0.040% P, max. 0.040% S.
  • FeNi25CS: 20 to 28% Ni (+Co), max. 2.0% C, max. 2.0% Cr, max. 4.0% Si, max.0.040% P, max. 0.30% S.
  • FeNi55: 50 to 60% Ni (+Co), max. 0.05% C, max. 0.050% Cr, max. 1.0% Si, max.0.020% P, max. 0.010% S.

Ferroniobium
Iron-niobiummaster alloy, standardized in DIN 17 569 (May 1982), as:

  • FeNb63 with 58 to 68% Nb.
  • FeNb65 with 63 to 68% Nb.
  • FeNb65Ta0.2 with 63 to 68% Nb and max. 0.2% Ta.

Ferrophosphorus
Iron-phosphorus master alloy used a phosphorus carrier in iron casting. Ferrophosphorus is produced in an electric furnace and has about the following composition: 18.0 to 24.0% P, 0.5 to 0.75% Si, max. 0.25% C, the rest being Fe.

Ferrosilicon
Iron-silicon master alloy (also used as an inoculation alloy), standardized according to DIN 17 560, as:

  • FeSi10: 8.0 to 15% Si, max. 0.8% Al, max. 0.15% P, max. 2.5% C.
  • FeSi25: 20.0 to 30.0% Si, max. 0.8% Al, max. 0.08% P, max. 0.8% C.
  • FeSi45: 42.0 to 48.0% Si, max. 1.5% Al, max. 0.05% P, max. 0.2% C.
  • FeSi75: 73.0 to 79.0% Si, 1.0 to 2.0% Al, max. 0.05% P, max. 0.1% C.
  • FeSi75-Al1: 73.0 to 79.0% Si, max. 1.0% Al, max. 0.05% P, max. 0.1% C.
  • FeSi90: 87.0 to 95.0% Si, 1.0 to 2.5% Al, max. 0.04% P, max. 0.1% C.
  • FeSi90-Al1: 87.0 to 95.0% Si, max. 1.0% Al, max. 0.04% P, max. 0.1% C.

Ferrotantalum
Iron-tantalummaster alloy containing approx. 75 to 80% tantalum.

Ferrotantalum-niobium
Tantalum-niobium-iron master alloy with a total content of 70 to 80% Ta+Nb, the rest being Fe.

Ferrotitanium
Iron-titaniummaster alloy, standardized according to DIN 17 566, as:

  • FeTi30: 28 to 32% Ti, max. 4.5% Al, max. 4.0% Si, max. 1.5% Mn, max. 0.10% C, max. 0.050% P, max. 0.060% S.
  • FeTi40: 36 to 40% Ti, max. 6.0% Al, max. 4.5% Si, max. 1.5% Mn, max. 0.10% C, max. 0.10% P, max. 0.060% S.
  • FeTi50: 46 to 50% Ti, max. 7.5% Al, max. 4.0% Si, max. 1.0% Mn, max. 0.10% C, max. 0.10% P, max. 0.060% S.
  • FeTi70: 65 to 70% Ti, max. 2.0% Al, max. 0.20% Si, max. 1.0% Mn, max. 0.20% C, max. 0.040% P, max. 0.030% S.
  • FeTi70VB (vacuum-degassed): 65 to 75% Ti, max. 0.50% Al, max. 0.10% Si, max. 0.20% Mn, max. 0.20% C, max. 0.030% P, max. 0.030% S.

Ferrovanadium
Vanadium-iron master alloy, standardized according to DIN 17 563, as:

  • FeV60: 50 to 65% V, max. 2.0% Al, max. 1.5% Si.
  • FeV80: 78 to 82% V, max. 1.5% Al, max. 1.5% Si.

Ferrotungsten
Tungsten-iron master alloy, standardized according to DIN 17 562, as:

  • FeW80: 75 to 85% W, max. 1.0% C, max. 0.6% Si, max. 0.6% Mn, max. 0.2% Cu.

Ferrozirconium-silicon
Alloy with 35 to 40% Zr, 40 to 50% Si, max. 2.5% Mn, max. 0.2% C, the rest being Fe.