Description of Ferrochrome
Ferrochrome (FeCr) is a ferroalloy composed of chromium and iron. It is an important alloy agent in steelmaking. According to different carbon content, Ferrochrome is divided into High Carbon Ferrochrome (carbon content of 4~8%), Medium Carbon Ferrochrome (carbon content of 0.5~4%), Low Carbon Ferrochrome or lc ferro chrome (carbon content of 0.15~0.50%), Micro Carbon Ferrochrome (with a carbon content of 0.06%), Ultra-Fine Carbon Ferrochrome (with a carbon content of less than 0.03%), as well as silicon-chromium alloy, nitride ferrochromium, etc.
Specification of Ferrochrome
| Classification | Model | Chemical Component/% | |||||||||
| Cr | C | Si | P | S | |||||||
| Range | Ⅰ | Ⅱ | Ⅰ | Ⅱ | Ⅰ | Ⅱ | Ⅰ | Ⅱ | |||
| ≥ | ≤ | ||||||||||
| Micro Carbon Ferro Chrome | FeCr69C0.03 | 63.0-75.0 | – | – | 0.03 | 1 | – | 0.03 | – | 0.25 | – |
| FeCr55C3 | – | 60 | 52 | 0.03 | 1.5 | 2 | 0.03 | 0.04 | 0.03 | – | |
| FeCr69C0.06 | 63.0-75.0 | – | – | 0.06 | 1 | – | 0.03 | – | 0.25 | – | |
| FeCr55C6 | – | 60 | 52 | 0.06 | 1.5 | 2 | 0.04 | 0.06 | 0.03 | – | |
| FeCr69C0.10 | 63.0-75.0 | – | – | 0.1 | 1 | – | 0.03 | – | 0.25 | – | |
| FeCr55C10 | – | 60 | 52 | 0.1 | 1.5 | 2 | 0.04 | 0.06 | 0.03 | – | |
| FeCr69C0.15 | 63.0-75.0 | – | – | 0.15 | 1 | – | 0.03 | – | 0.25 | – | |
| FeCr55C15 | – | 60 | 52 | 0.15 | 1.5 | 2 | 0.04 | 0.06 | 0.03 | – | |
| Low Carbon Ferro Chrome | FeCr69C0.25 | 63.0-75.0 | – | – | 0.25 | 1 | – | 0.03 | – | 0.25 | – |
| FeCr55C25 | – | 60 | 52 | 0.25 | 1.5 | 3 | 0.04 | 0.06 | 0.03 | 0.05 | |
| FeCr69C0.50 | 63.0-75.0 | – | – | 0.5 | 1 | – | 0.03 | – | 0.25 | – | |
| FeCr55C50 | – | 60 | 52 | 0.5 | 1.5 | 3 | 0.04 | 0.06 | 0.03 | 0.05 | |
| FeCr69C1.0 | 63.0-75.0 | – | – | 1 | 1 | – | 0.03 | – | 0.25 | – | |
| FeCr55C100 | – | 60 | 52 | 1 | 1.5 | 3 | 0.04 | 0.06 | 0.03 | 0.05 | |
| FeCr69C2.0 | 63.0-75.0 | – | – | 2 | 1 | – | 0.03 | – | 0.25 | – | |
| FeCr55C200 | – | 60 | 52 | 2 | 1.5 | 3 | 0.04 | 0.06 | 0.03 | 0.05 | |
| FeCr69C4.0 | 63.0-75.0 | – | – | 4 | 1 | – | 0.03 | – | 0.25 | – | |
| FeCr55C400 | – | 60 | 52 | 4 | 1.5 | 3 | 0.04 | 0.06 | 0.03 | 0.05 | |
| High Carbon Ferro Chrome | FeCr67C6.0 | 62.0-72.0 | – | – | 6 | 1 | – | 0.03 | – | 0.04 | 0.06 |
| FeCr55C600 | – | 60 | 52 | 6 | 1.5 | 5 | 0.04 | 0.06 | 0.04 | 0.06 | |
| FeCr67C9.5 | 62.0-72.0 | – | – | 9.5 | 1 | – | 0.03 | – | 0.04 | 0.06 | |
| FeCr55C1000 | – | 60 | 52 | 10 | 1.5 | 5 | 0.04 | 0.06 | 0.04 | 0.06 | |
Classification of Ferrochrome
Ferrochromium is a ferroalloy with chromium and iron as the main components. It is one of the main alloying agents used in the iron and steel industry. In addition to the main components of chromium and iron, it also contains impurities such as carbon, silicon, sulfur, and phosphorus.
FeCr contains 55% to 75% chromium and is divided into high carbon (4% to 10% C), medium carbon (0.5% to 4% C), low carbon (>0.15% to 0.5% C), and low carbon (>0.15% to 0.5% C) according to the carbon content. Micro-carbon (≤0.15%C) FeCr metal.
Ferrochrome high carbon is also called carbon ferrochrome, and medium, low, and micro-carbon ferrochrome alloy is also called refined ferrochromium. High-carbon ferrochrome produced from chrome ore with a low chromium-to-iron ratio, containing 50% to 55% of Cr is called charge-grade ferrochrome alloy, and nitrogen-containing ferrochromium containing N2% to 10% is used as a nitrogen alloying agent.
Application of FeCr
The addition of chromium to steel can significantly improve the oxidation resistance of steel and increase the corrosion resistance of steel. Chromium is contained in many sheets of steel with special physical and chemical properties. Chromium in steel is added with ferrochromium.
High carbon ferrochrome is used as an alloying agent for ball steel (0.5%～1.45%Cr), tool steel, die steel (5%～12%Cr), and high-speed steel (3.8%～4.4%Cr), which can improve the quenching of steel. permeability, increase the wear resistance and hardness of steel. Adding chromium to cast iron can increase hardness and improve wear resistance, and chromium content of 0.5% to 1.0% can improve its mechanical properties. High carbon FeCr alloy and charge grade ferrochromium is used in large quantities as the charge for smelting stainless steel (AOD or VOD method) to reduce production costs.
Medium and ferro chrome low carbon is used in the production of medium and low-carbon structural steel, carburized steel, gears, high-pressure blower blades, valve plates, etc.
Micro-carbon ferrochrome is used in the production of stainless steel, acid-resistant steel, heat-resistant steel, and electrothermal alloys.
Case Study
Background
An integrated stainless steel plant in Indonesia, producing 400,000 tonnes per year of austenitic grade 304 (18% Cr, 8% Ni) and ferritic grade 430 (16–18% Cr), was facing two persistent challenges. First, their chromium recovery rate from the electric arc furnace (EAF) melting process was only 82%, well below the industry benchmark of 90–92%. Second, slag volumes were excessive, leading to higher refractory wear and increased energy consumption. The plant had been using a mix of low-carbon ferrochrome (LC FeCr) and charge chrome, but the cost structure was becoming unsustainable as chrome ore prices fluctuated.
Objective
Increase chromium recovery to at least 90%, reduce slag generation by 15%, and lower total alloy cost per tonne of liquid steel without compromising final product chemistry or inclusion cleanliness.
Root Cause Analysis
An internal audit revealed two main issues. First, the plant was over-specifying low-carbon ferrochrome for applications where high-carbon ferrochrome (HC FeCr) would be equally suitable. Second, improper addition timing-adding FeCr too early in the melt-led to chromium oxidation into the slag, especially during periods of high oxygen input from scrap melting. The slag contained 8–10% Cr₂O₃, representing a direct financial loss.
Solution Implemented
The plant switched to a two-step strategy:
Alloy substitution: For grade 304 (where carbon up to 0.08% is acceptable), they replaced 70% of LC FeCr with high-carbon ferrochrome (HC FeCr) containing 52–54% Cr, 6–8% C, and 3–5% Si. HC FeCr cost 18% less per kilogram of contained chromium than LC FeCr.
Addition protocol redesign: HC FeCr was added late in the melt-after the scrap had fully melted and oxygen lancing had ceased-using a bucket addition directly into the ladle during tapping, combined with strong argon stirring to promote dissolution and prevent reoxidation.
For grade 430, which has a tighter carbon specification (max 0.08% C), they retained LC FeCr but still applied the late-addition principle.
Results
After a four-month trial across 450 heats:
Chromium recovery: Increased from 82% to 91.5% on average, peaking at 93% for optimized heats.
Slag chemistry: Cr₂O₃ in slag dropped from 8–10% to 2.5–4%. Total slag volume reduced by 22% due to less chromium oxide formation and lower lime requirements.
Energy consumption: EAF power use fell by 9 kWh per tonne because less energy was wasted reheating oxidized chromium.
Refractory life: Furnace lining wear decreased by 15%, extending campaign life from 450 to 520 heats.
Final product quality: No difference in corrosion resistance, surface finish, or mechanical properties between heats made with HC FeCr versus LC FeCr in grade 304. Inclusion ratings remained within ASTM A240 limits.
Cost-Benefit Analysis
| Metric | Before (LC FeCr) | After (HC FeCr blend) |
|---|---|---|
| Chromium recovery | 82% | 91.5% |
| Alloy cost per tonne steel | $187 | $162 |
| Refractory cost per tonne | $8.50 | $7.20 |
| Energy cost per tonne | $31 | $29.50 |
The plant achieved annual savings of $9.2 million, broken down as:
$7.5 million from lower alloy purchase costs
$1.2 million from improved recovery (less chromium lost to slag)
$0.5 million from refractory and energy savings
Conclusion
This case demonstrates that high-carbon ferrochrome, when applied with disciplined addition timing and ladle metallurgy practices, can significantly outperform more expensive low-carbon grades in austenitic stainless steel production. The key is matching the alloy to the application-using HC FeCr where carbon specifications permit-and adding it at the correct moment to minimize oxidation. For this Indonesian plant, switching to an HC FeCr-dominant strategy not only improved recovery and reduced costs but also enhanced overall process stability and refractory life.
Hot Tags: ferrochrome, China ferrochrome manufacturers, suppliers, factory, Calcium Silicon Casi Alloy, Ferro Silicon Barium Fesiba, Silicon Carbon Alloy, Silicon Series, Silicon Slag, Silicon Slag To Replace Fesi And Reduce The Cost
