Start with an existing metal melt or alloy, enter its current composition and target percentage, then calculate how much concentrated addition material is needed to reach the target.
What this calculation means
Starting element mass
The calculator first determines how much of the selected element is already present in the starting material.
Required addition
The required addition is solved from the final mass balance after the addition material is introduced.
Final melt
The final melt mass equals starting material plus addition material. The resulting element percentage is checked against the requested target.
Recovery below 100% increases the required addition because only part of the addition's theoretical element contribution is assumed to remain available in the melt.
Common alloy adjustment examples
- Copper adjustment: raise copper concentration in a lower-copper starting alloy using a high-copper addition.
- Chromium adjustment: add chromium-bearing material to move a steel melt toward a specified chromium level.
- Carbon adjustment: estimate a carbon addition for a steel melt when the addition chemistry is known.
- Magnesium adjustment: estimate magnesium-bearing addition required for an aluminum melt.
- Nickel adjustment: calculate a nickel-bearing addition for a target nickel concentration.
- Silicon adjustment: estimate silicon-bearing additions when increasing silicon content.
Actual furnace additions can require simultaneous balancing of several elements. Oxidation, slag/dross formation, dissolution efficiency, contamination and material chemistry can change the actual result.
Formula used
With 100% recovery
Addition mass = Starting mass × (Target − Current) ÷ (Addition concentration − Target)
With recovery below 100%
The effective addition concentration is treated as Addition concentration × Recovery. The calculation then solves the final mass balance using that effective contribution.
The target must be greater than the starting concentration when using an addition whose effective concentration is above the target. If the starting melt is already above target, dilution or a different charge strategy is normally required.
Frequently Asked Questions
How do I calculate an alloy addition?
Enter the starting melt mass, current concentration, target concentration, addition material concentration and estimated recovery. The calculator solves the required addition mass.
Why does adding an alloy change the target calculation?
The addition itself becomes part of the final melt mass. Therefore the target concentration must be calculated against the new total mass, not just the original starting mass.
What if the addition is 100% pure metal?
Enter 100% as the addition concentration. The calculator then treats the addition as pure selected element before applying the recovery assumption.
What if the current composition is already above the target?
A positive addition cannot normally lower the concentration unless the addition material is more dilute than the current material. The calculator identifies whether the requested adjustment is mathematically possible.
What does recovery mean in alloying?
Recovery represents the portion of the theoretical element contribution that is assumed to become available in the final melt. Actual recovery is process-dependent.
Can this calculate master alloy additions?
Yes. Enter the actual percentage of the selected element in the master alloy or other addition material.
Is this suitable for final production chemistry?
No calculator should replace actual chemistry verification. Use certified material analysis, laboratory testing and established furnace practice for production decisions.