EN
Introduction
Wollastonite powder is a natural non-metallic mineral material mainly composed of calcium metasilicate (CaSiO₃), characterized by acicular crystal structure, white color, low oil absorption and high chemical stability. As a high-performance functional filler, it is widely used in ceramics, plastics, rubber, coatings, metallurgy and construction materials with unique needle-like structure and excellent physical and chemical properties.
1. Formation & Production of Wollastonite
Wollastonite is formed by regional metamorphism and contact metamorphism of limestone or dolomite in the presence of silicarich fluids over long geological periods. Industrial wollastonite is processed through mining, crushing, grinding, classification, purification and surface modification to remove impurities such as quartz and calcite. The final powder retains its natural acicular shape, high aspect ratio and stable composition.
2. Key Characteristics of Wollastonite
- Acicular Structure & High Aspect Ratio: Typical needlelike crystal shape provides high reinforcement, rigidity and dimensional stability.
- High Whiteness & Low Oil Absorption: High brightness and whiteness, low oil absorption rate, reduces resin consumption and improves dispersion.
- Excellent Mechanical Properties: Improves hardness, tensile strength, flexural strength and wear resistance of composite materials.
- High Thermal Stability & Low Thermal Expansion: Stable at high temperature, low shrinkage, resistant to cracking and deformation.
- Good Electrical Insulation: High resistivity, low dielectric loss, suitable for electrical and electronic materials.
- Chemical Stability: Acid and alkali resistant, insoluble in water, nontoxic, odorless and environmentally friendly.
3. Main Application Fields of Wollastonite
3.1 Ceramics Industry (Core Application)
Used in ceramic bodies and glazes to reduce firing shrinkage, improve firing stability, enhance strength and whiteness, and lower firing temperature. Widely used in tableware, wall and floor tiles, sanitary ware and technical ceramics.
3.2 Plastics & Composites
As a reinforcing filler in PP, PA, PVC, ABS and engineering plastics to improve rigidity, heat resistance, dimensional stability and surface smoothness. Used in auto parts, electronic housings, profiles and fibers.
3.3 Coatings & Paints
Improves coating hardness, weather resistance, scrub resistance and corrosion resistance. Reduces settling and improves leveling. Used in architectural coatings, industrial coatings and anticorrosion coatings.
3.4 Rubber Industry
Enhances tensile strength, tear resistance and wear resistance of rubber products. Improves processing performance and reduces production cost. Used in tires, seals, hoses and rubber sheets.
3.5 Metallurgy & Welding Materials
Used as a fluxing component in welding electrodes and welding wires to improve slag fluidity, arc stability and weld formation. Also used in metallurgical fluxes and refractory materials.
3.6 Construction & Other Fields
Applied in cement, friction materials, paper making, environmental protection materials and insulation panels to enhance performance and reduce costs.
4. Standards for High-Quality Wollastonite Selection
- High Aspect Ratio: Long needle structure, obvious reinforcing effect.
- High Whiteness & Purity: Low iron and impurity content, no yellowing or darkening.
- Uniform Particle Size: Narrow particle distribution, good dispersion and processability.
- Surface Activity: Suitable surface modification improves compatibility with polymers.
- Stable Performance: Consistent batch quality, certified by ISO and industry standards.
5. Comparison with Talc, Calcium Carbonate & Kaolin
Wollastonite is superior in acicular reinforcement, rigidity and dimensional stability, better than calcium carbonate and talc in structural performance. Talc provides better lubricity; calcium carbonate is more costeffective; kaolin has better plasticity. Wollastonite is the first choice for highstrength reinforced plastics, ceramics and engineering composites.
Conclusion
Wollastonite powder is a highperformance functional mineral filler with unique acicular morphology, high strength, thermal stability and low oil absorption. It plays an important role in ceramics, plastics, coatings, rubber and metallurgy, and is widely used in highperformance manufacturing worldwide.
We provide wollastonite powder with various particle sizes, aspect ratios and surface treatments. Customized processing and free samples are available. With stable supply, reliable quality and professional export service, we are looking forward to establishing longterm cooperation with global customers.