Июл . 09, 2025 15:50
Wollastonite powder, derived from the naturally occurring calcium silicate mineral wollastonite, is a versatile industrial material prized for its unique combination of physical and chemical properties. Characterized by its acicular (needle-like) or fibrous structure, high brightness, and low moisture absorption, it has become a staple in numerous manufacturing processes.
Chemically, wollastonite powder consists primarily of calcium oxide (CaO) and silicon dioxide (SiO₂), with trace amounts of other oxides. This composition grants it exceptional thermal stability, resistance to chemical corrosion, and low thermal conductivity, making it a preferred additive in heat-resistant applications. Its needle-like morphology—typically with high aspect ratios—enhances mechanical strength when incorporated into composites, acting as a reinforcing agent that improves tensile and impact resistance.
The production of wollastonite powder involves crushing, grinding, and classification to achieve precise particle sizes, ranging from microscale to nanoscale, depending on the intended use. Surface treatment processes, such as coating with silanes or stearates, can further enhance its compatibility with polymers, ceramics, and other matrix materials, optimizing dispersion and bonding.
In the plastics industry, wollastonite powder serves as a cost-effective filler in products like polypropylene and polyethylene, reducing shrinkage, improving dimensional stability, and enhancing flame retardancy. Its low oil absorption also makes it ideal for increasing the load of pigments in plastic formulations without compromising material flow during processing.
Within the ceramics sector, wollastonite powder acts as a flux, lowering firing temperatures and reducing energy consumption while improving the strength and whiteness of ceramic bodies. It is widely used in the production of tiles, sanitaryware, and electrical insulators, where its ability to minimize warping and cracking during sintering is highly valued.
In the construction industry, wollastonite powder enhances the performance of cement and concrete by accelerating hydration, increasing compressive strength, and reducing permeability. It also finds application in drywall compounds, where it improves workability and reduces drying time.
Other key uses include as a reinforcing agent in friction materials (such as brake pads), a filler in paints and coatings to enhance scrub resistance and opacity, and as a component in metallurgical fluxes for steelmaking.