Q1: Why does FeSi75 particle size matter so much?
Because FeSi75 only creates value after it actually dissolves and reacts in the melt. Size changes three practical things:
melting speed (how fast it reacts)
loss (dust/fines blowing away, sticking to surfaces, or being trapped in slag)
control (how easy it is to dose and hit your target without overshooting)
So size affects your "real cost per effective silicon," not just the quoted price per ton.
Q2: What are the common export size ranges for FeSi75?
Most buyers see these ranges again and again:
| FeSi75 Form | Typical Size Range | What It's Usually Chosen For |
|---|---|---|
| Lumps | 10–50 mm | steady melting, easier handling |
| Lumps | 10–100 mm | bulk use, slower response |
| Granules | 3–10 mm | balanced speed and control |
| Granules | 1–5 mm | faster correction, tighter timing |
| Fines | 0–3 mm | special use; higher loss risk if not intended |
If your supplier can't clearly state the size range and fines level, the "size" is not really controlled.
Q3: When should you choose lumps instead of granules?
Lumps are often the better choice when:
you add FeSi earlier (furnace or tapping) and your melt has time
you want lower dust loss and cleaner handling
your process is stable and you don't need "fast reaction"
you care about storage and transport durability
Lumps typically behave calmly. They may feel slower, but they can be very efficient if your timing allows it.
Q4: When do granules give better results?
Granules are usually the smarter choice when:
you need FeSi to dissolve quickly
you do late adjustments and want a faster response
you use automated feeding and need consistent flow
you want tighter control for small corrections
Granules often make recovery feel more repeatable. The tradeoff is they need good packing and handling to avoid extra fines.
Q5: If smaller dissolves faster, why not always pick 0–3 mm or very fine sizes?
Because speed can become waste. Very fine material:
creates more dust during unloading and feeding
can oxidize faster in humid conditions
is easier to lose before it ever reaches the melt
may react too quickly in turbulent conditions and increase slag-related loss
So the best size is the one that fits your addition point. Fast is useful only when it's controlled.
Q6: What should you confirm to avoid "size surprises" after arrival?
This is where many disputes start. Two shipments can both be called "10–50 mm," but behave differently if the fines content is not controlled.
A simple purchase checklist:
| Item to Confirm | Why It Matters |
|---|---|
| Exact size range | avoids mixed melting speed |
| Maximum fines percentage | reduces loss and dust complaints |
| Packing type (jumbo / small bags) | affects breakage and moisture risk |
| COA items + lot consistency | keeps performance stable |
| Loading port + shipment window | avoids timing stress and rushed packing |
Our FeSi Supply
We supply FeSi75 (also FeSi72 / FeSi65 / FeSi45) in common export sizes such as 10–50 mm, 10–100 mm, 3–10 mm, 1–5 mm, and 0–3 mm, with stable screening and export-ready packing.
If you want the quickest, most accurate quotation, just send these 4 lines:
Grade: FeSi75 / FeSi72 / FeSi65 / FeSi45
Size: (e.g., 10–50 mm or 3–10 mm) + max fines % if you have it
Quantity & packing: jumbo bags or 25 kg bags
Destination port & target shipment time
We'll reply with the recommended spec (if needed) and a workable FOB/CIF quote based on your shipping window.
