Wollastonite, a calcium silicate mineral, finds various industrial applications due to its unique physical and chemical properties. Some of its main uses include:
Ceramics Industry
Wollastonite is commonly used as a filler and flux in ceramic formulations. Its high melting point, low thermal expansion coefficient, and excellent whiteness make it ideal for enhancing the strength, durability, and thermal shock resistance of ceramic products such as tiles, sanitaryware, and refractory materials.
Plastics and Polymers
In the plastics industry, wollastonite serves as a reinforcing filler, improving the mechanical properties (such as tensile strength, modulus, and dimensional stability) of plastic composites. It also acts as a nucleating agent, enhancing crystallization and reducing shrinkage during processing. Additionally, wollastonite-filled polymers exhibit improved flame retardancy and thermal stability.
Construction Materials
Wollastonite is utilized in various construction materials, including concrete, mortar, and stucco, to enhance their strength, durability, and workability. Its fibrous morphology provides reinforcement, reducing cracking and improving the overall performance of these materials.
Paints and Coatings
Due to its high brightness, low oil absorption, and chemical inertness, wollastonite is used as a functional extender and opacifier in paints, coatings, and adhesives. It enhances coating durability, scrub resistance, and weatherability while also reducing costs by replacing more expensive pigments and fillers.
Friction Products
Wollastonite’s high hardness, low abrasiveness, and heat resistance make it suitable for use in friction materials such as brake pads, clutch linings, and friction tiles. It improves the frictional properties, wear resistance, and thermal stability of these products, contributing to enhanced safety and longevity in automotive and industrial applications.
Agricultural and Environmental Applications
Wollastonite is sometimes used in agriculture to supply calcium and silicon to plants, improve soil pH, and enhance nutrient availability. Additionally, its alkaline nature can be utilized in environmental remediation efforts to neutralize acidic soils and industrial waste streams.
Overall, the versatile properties of wollastonite make it a valuable additive in various industries, contributing to the performance, sustainability, and cost-effectiveness of a wide range of products and applications.