Kyanite
High-alumina kyanite with irreversible volume expansion for shrinkage compensation in castables, mortars, high-alumina bricks, and precision foundry cores.
Product Overview: High-Alumina Kyanite
Kyanite is an aluminosilicate mineral (Al2SiO5) renowned for its characteristic volume expansion upon heating to mullite at high temperatures, counteracting the natural shrinkage of refractory binders and clays.
With high alumina content (Al2O3 ≥ 55–60%), extreme refractoriness (PCE > 36), and superior thermal shock resistance, Sakthima Kyanite is widely specified for monolithic refractories, refractory bricks, precision casting moulds, and high-duty spark plug ceramics.
Key Benefits
Prevents Cracking & Shrinkage
Irreversible 16% volume expansion during mullitization offsets the firing shrinkage of refractory castables and mortars.
Interlocked Needle Toughness
Forms a tight network of interlocking mullite needles that imparts superior mechanical strength and creep resistance.
High Thermal Shock Resistance
Maintains dimensional stability under rapid furnace cycling, minimizing spalling and thermal cracking.
Precision Investment Casting
Provides smooth surface finish and dimensional precision for high-temperature alloy casting moulds.
High Dielectric Strength
Used in technical ceramics, high-voltage insulators, and spark plugs for its non-conductive properties.
Applications
Monolithic Refractory Castables
High-Alumina Fire Bricks
Precision Foundry Shell Moulds
Automotive Brake Pads & Friction
Technical Specifications
| Parameter | Premium K-60 | Standard K-58 | Refractory K-55 | Ceramic K-50 | Utility Grade |
|---|---|---|---|---|---|
| Alumina (Al2O3) | 60.2% | 58.5% | 55.2% | 50.8% | 45.0% |
| Silica (SiO2) | 36.5% | 38.2% | 41.0% | 45.5% | 50.0% |
| Iron Oxide (Fe2O3) | 0.6% | 0.9% | 1.2% | 1.6% | 2.5% |
| Titanium (TiO2) | 0.9% | 1.2% | 1.5% | 1.8% | 2.2% |
| LOI | < 0.5% | < 0.8% | < 1.0% | < 1.2% | < 2.0% |
| PCE (Orton Scale) | 36-37 | 35-36 | 33-34 | 31-32 | 28-29 |
| Thermal Expansion | 1.2% | 1.3% | 1.4% | 1.5% | 1.8% |
| Mesh Size | 325 Mesh | 200 Mesh | 200 Mesh | 100 Mesh | 100 Mesh |
Why Choose Us?
High Alumina Grade Deposits
Processed from high-grade bladed kyanite ores with minimal quartz and iron oxide impurities.
Multiple Mesh Gradings
Supplied in 35 Mesh, 48 Mesh, 100 Mesh, 200 Mesh, and 325 Mesh for diverse formulations.
Low Iron & Alkalies
Strict magnetic separation ensures Fe2O3 < 0.8% and total alkalies (Na2O + K2O) < 0.5%.
Dependable Industrial Deliveries
Available in 50 kg HDPE bags and 1 MT jumbo bags with consistent nationwide logistics.