Silicon Carbide 88% (SiC ≥88%) is the mainstream mid-purity metallurgical-grade silicon carbide, widely adopted across global electric arc furnaces, induction melting lines, and refractory manufacturing plants. It delivers balanced metallurgical performance, stable high-temperature resistance, and far lower raw material costs compared to high-purity SiC90, SiC95 or abrasive-grade green silicon carbide.
SiC88 serves dual core industries: steelmaking as a composite deoxidizer, carburizer and heat booster; refractories as a high-temperature aggregate for furnace linings, castables and SiC bricks.
Standard Chemical Specifications of SiC 88%
| Index | Standard Value of SiC 88% | Practical Impact |
|---|---|---|
| SiC Content | ≥88.0% | Sufficient silicon-carbon activity for deoxidation & refractory strength |
| Free Carbon (F.C.) | ≤4.0% | Avoid excess carbon causing carbon overshoot in molten steel |
| Fe₂O₃ | ≤3.0% | Limit brittle iron impurities to protect steel ductility & refractory anti-corrosion |
| Al₂O₃ | ≤1.5% | Prevent low-melting eutectic formation at high temperatures |
| Moisture | ≤0.5% | Eliminate molten metal splashing during furnace feeding |
| Usable Temperature | Up to 1650°C | Stable structure for long-term high-temperature service |
Core Benefits of SiC 88% for Steelmaking
In EAF, LF ladle refining and induction furnace production, SiC88 replaces separate ferrosilicon and carburizer, bringing multiple cost and quality advantages verified by mass smelting data.
2.1 Triple-Function Composite Deoxidizer
SiC decomposes under molten steel heat to release active silicon and carbon, completing three tasks in one material:
Deep deoxidation: Silicon reacts with dissolved oxygen to form stable SiO₂ slag, cutting blowhole and inclusion defects in steel billets.
Controllable carburizing: Free carbon supplements molten steel carbon without sharp composition fluctuations.
Exothermic heating agent: The redox reaction releases large heat, raising molten steel temperature and reducing furnace power consumption by 8–12%.
2.2 Cut Consumption of Traditional Ferrosilicon by 15–30%
Unlike FeSi75 that only relies on silicon for deoxidation, SiC88's dual silicon-carbon reduction capacity improves deoxidation efficiency. Steel mills can reduce FeSi purchasing volume significantly, lowering overall alloy raw material expenditure.
2.3 Stable Molten Steel Composition & Lower Scrap Rate
SiC88 features mild, controllable reaction without violent splashing or severe silicon volatilization. It avoids over-silicon or over-carbon defects, stabilizes mechanical indicators of carbon steel and low-alloy steel, and reduces defective casting billet rates.
2.4 Optimize Slag Fluidity & Extend Ladle Lining Life
Generated SiO₂ improves slag viscosity and desulfurization capacity, reducing slag erosion on ladle refractory linings. Factories report 15–20% longer service cycles for ladle walls after switching to SiC88 deoxidizer.
Key Advantages of SiC 88% for Refractory Manufacturing
SiC88 is the most cost-effective aggregate for general metallurgical refractories, balancing thermal shock resistance and procurement cost compared to higher-purity SiC grades.
3.1 Excellent Thermal Shock Resistance & Low Thermal Expansion
SiC crystal structure delivers low thermal expansion coefficient and high thermal conductivity. Refractory bricks/castables mixed with SiC88 resist repeated rapid heating and cooling cycles, effectively preventing lining cracking and spalling in EAF and blast furnaces.
3.2 Strong Slag & Molten Metal Corrosion Resistance
SiC is chemically inert against acid and alkaline slag at high temperatures. SiC88 aggregates form a dense protective layer inside refractories, slowing molten iron/slag penetration and erosion on furnace working surfaces.
3.3 Reduce Refractory Production Cost Without Sacrificing Durability
SiC90 and SiC95 carry obvious premium pricing. For conventional furnace linings, runner castables and medium-temperature kiln refractories, SiC88 fully meets performance requirements while cutting raw material cost by 10–18% per ton of refractory products.
3.4 Improve Refractory Mechanical Strength & Wear Resistance
Adding graded SiC88 particles increases refractory bending strength and abrasion resistance, suitable for high-flow molten iron channels, furnace bottom working layers and continuous casting tundish linings.
SiC 88% vs. Other Common SiC Grades
| Grade | SiC Purity | Main Application | Core Advantage | Shortcomings |
|---|---|---|---|---|
| SiC 88% | ≥88% | General steelmaking, standard refractories | Low unit price, balanced activity & heat resistance | Not for ultra-purity special steel / ultra-high temperature kilns |
| SiC 90% | ≥90% | High-cleanliness steel, heavy-duty refractories | Lower impurities, longer lining life | 10–15% higher cost than SiC88 |
| SiC 95% | ≥95% | Precision casting, high-temperature industrial kilns | Ultra-low oxide impurities | High procurement cost, uneconomical for mass production |
| Black Abrasive SiC 97% | ≥97% | Grinding tools only | High hardness | Too expensive for metallurgy & refractories |
Matching Guidance
Choose SiC88: Ordinary carbon steel, construction steel, gray iron casting, blast furnace general lining, medium-temperature castables, mass production with strict raw material budgets.
Upgrade to SiC90: Pipeline steel, high-alloy steel, EAF severe slag erosion zones, long-campaign furnace linings.
Practical Usage Tips to Maximize SiC88 Benefits
For Steelmaking
Select size 3–10mm for LF ladle deoxidation; 10–30mm for EAF furnace batch feeding.
Add SiC88 after oxidation slag removal to avoid early oxidation loss.
Store in dry sealed warehouses; moisture causes splashing and weakens deoxidation effect.
Check CoA for each batch to stabilize silicon and carbon control.
For Refractory Production
Mix multi-grade SiC88 particles (coarse + medium + fine powder) to improve refractory compactness.
Match suitable binding agents to maximize thermal shock resistance of finished refractory products.
Avoid mixing SiC88 with high-impurity low-grade SiC to prevent lining performance degradation.
SiC 88% remains the most cost-efficient silicon carbide grade for mainstream steelmaking and refractory production. In steel plants, it acts as an all-in-one deoxidizer, carburizer and heat booster, cutting ferrosilicon consumption and reducing casting defects. In refractory manufacturing, it provides reliable thermal shock and anti-corrosion performance at a far lower price than SiC90/SiC95.
For factories producing standard carbon steel, structural steel, general cast iron and conventional metallurgical refractories, SiC88 delivers the optimal balance of stable metallurgical performance and long-term raw material cost savings. Only high-end special steel and ultra-severe high-temperature kiln projects need to upgrade to higher-purity SiC grades.
