What is Green Silicon Carbide?
Green silicon carbide (SiC) is a high-purity, synthetic mineral produced in an electric resistance furnace from a mixture of high-quality silica sand and petroleum coke, with salt as a catalyst. Its distinctive green color comes from its exceptional purity (over 99% SiC), as it contains fewer metallic impurities than its black silicon carbide counterpart.
| TYPICAL CHEMICAL ANALYSIS | |
| SiC | ≥99.05% |
| SiO2 | ≤0.20% |
| F,Si | ≤0.03% |
| Fe2O3 | ≤0.10% |
| F.C | ≤0.04% |
| TYPICAL PHISICAL PROPERTIES | |
| Hardness: | Mohs：9.5 |
| Melting Point: | Sublimes at 2600 ℃ |
| Maximum service temperature: | 1900℃ |
| Specific Gravity: | 3.20-3.25g/cm3 |
| Bulk density(LPD): | 1.2-1.6 g/cm3 |
| Color: | Green |
| Particle shape: | Hexagonal |
| 型号： | |
| Grit：4# 5# 6# 8# 10# 12# 14# 16# 20# 22# 24# 30# 36# 40# 46# 54# 60# 70# 80# 10# 12# 14# 16# 20# 22# 24# 30# 36# 40# 46# 54# 60# 70# 80# 90# 100# 120# 150# 180# 220# Micropowder： JIS:240# 280# 320# 360# 400# 500# 600# 700# 800# 1000# 1200# 1500# 2000# 2500# 3000# 4000# 6000# 8000# 10000# FEPA： F230 F240 F320 F360 F400 F500 F600 F800 F1000 F1200 F1500 F2000 | |
Key Properties (Why it’s chosen for abrasives)
Green silicon carbide’s properties make it exceptionally well-suited for abrasive applications, particularly for hard, brittle, and low-tensile-strength materials.
Extreme Hardness: On the Mohs scale, it is a 9.5, second only to diamond (10) and boron carbide (9.75). This allows it to effectively cut and grind very hard materials.
High Brittleness & Sharpness: Its crystals fracture easily, creating new, sharp cutting edges throughout the tool’s life. This property, known as friability, is crucial for maintaining a sharp abrasive and preventing dullness.
Excellent Thermal Conductivity: It efficiently draws heat away from the grinding zone, reducing the risk of thermal damage to both the workpiece and the abrasive tool itself.
Chemical Inertness: It is relatively unreactive, making it suitable for use with coolants and on various materials without causing contamination.
Manufacturing of Abrasive Tools with Green SiC
Green SiC is rarely used as a monolithic block. Instead, it is crushed, milled, and precisely sized into grains (grit). These grains are then used to create various bonded and coated abrasive tools through different processes:
Vitrified Bonding (Most Common for Grinding Wheels):
The SiC grains are mixed with ceramic powders (the bond), pressed into the shape of a wheel, and fired in a kiln at high temperatures (≈1300°C).
The vitrified bond forms a glassy matrix that holds the grains firmly in place. This creates a rigid, porous, and strong grinding wheel.
Resinoid Bonding (for Cutting-off Wheels and Stronger Tools):
The grains are mixed with a synthetic resin (e.g., phenolic resin) and molded under heat and pressure.
Resin-bonded tools are more flexible and shock-resistant than vitrified ones, making them ideal for cutting operations and rough grinding.
Coated Abrasives (for Sandpaper, Flap Discs, etc.):
The grains are electrostatically oriented and glued onto a backing material (paper, cloth, or fiber).
This creates products like sanding belts, discs, and sheets used for finishing and stock removal.
Lapping and Polishing Compounds:
Fine and ultra-fine micron-sized powders of green SiC are suspended in water, oil, or grease.
This slurry is used for precision lapping to achieve extremely fine surface finishes and tight tolerances on materials like tungsten carbide.