1. Introduction
Silicon carbide (SiC) is a hard inorganic ceramic material with Mohs hardness up to 9.2, excellent thermal conductivity, outstanding chemical inertness and high-temperature resistance. Two main grades are applied in cookware: black silicon carbide (black SiC) and green silicon carbide (green SiC). Black SiC is widely adopted for dark stone-textured non-stick coatings due to its cost advantage and natural dark color.
Advantages
- Balanced abrasion resistance and thermal conductivity
- Cost-effective for dark non-stick coating systems
- Chemically stable against common food acids and alkalis
2. Main Application
It is the largest application in modern cookware manufacturing, used for frying pans, woks, grill plates, air fryer liners and oven bakeware. Coating systems include PTFE composite non-stick coatings, silicone ceramic coatings and sol-gel ceramic coatings.
silicon carbide functions in coating matrix
- Improve abrasion & scratch resistancePure PTFE is soft and vulnerable to scraping by metal utensils. Hard SiC particles form a rigid reinforcing framework inside the coating to bear friction loads, extending coating service life significantly.
- Enhance uniform heat conductionPTFE possesses low thermal conductivity. Embedded SiC optimizes heat distribution, reducing local overheating, coating yellowing and premature powdering during dry heating.
- Increase coating compactness & corrosion resistanceSiC micropowder fills microvoids in the coating, blocking penetration of acidic and alkaline food liquids, and lowering risks of blistering and peeling from the substrate.
- Provide color tone for aesthetic appearanceBlack SiC delivers dark grey / black tone, which is ideal for popular “marble stone effect” non-stick cookware without excessive black pigment. Green SiC is preferred for light-coloured ceramic coatings.
3. Secondary Applications in Cookware Production
- Substrate blasting & surface pretreatmentCoarse SiC grit is used for blasting aluminum and stainless steel cookware substrates to create rough surfaces, improving adhesion of subsequent non-stick coatings.
- Grinding and polishing mediaFine SiC micropowder is formulated into polishing slurries for deburring and matte finishing of stainless steel cookware and kitchen cutlery.
- Raw material for sharpening stonesSiC grains are manufactured into whetstones for sharpening kitchen knives.
4. Black SiC vs Green SiC for cookware coatings
| Item | Black Silicon Carbide | Green Silicon Carbide |
|---|---|---|
| SiC purity | ≥98%, minor free carbon | ≥99%, fewer impurities |
| Color | Dark grey / black | Light green |
| Toughness | Higher particle toughness | Higher hardness |
| Cost | Economical | Higher price |
| Typical usage | Dark marble-style non-stick coatings | Light-grey & pale ceramic coatings |