Silica fume for Refractory Casting

Introduction to Refractory Castables

Refractory materials, with their inherent ability to withstand high temperatures, play a pivotal role in various industries, from cooking ovens at 600°C to intense metal treatments surpassing 1700°C​​.

Role of Microsilica

Microsilica, or silica fume as it’s often termed, enhances the capabilities of these refractories. Comprising sub-micron particles, it enriches refractory products by aiding in efficient particle packing, facilitating the creation of self-flowing castables, and providing exceptional temperature and mechanical resilience​.

Silica fume for Refractory Casting Benefits

• Improved strength and durability: Silica fume can significantly increase the compressive strength, tensile strength, and flexural strength of refractory castables. This makes them more resistant to wear and tear, as well as to thermal shock and chemical attack.
• Reduced porosity: Silica fume fills the voids between the other constituents of refractory castables, resulting in a more dense and less porous material. This reduces the permeability of the castable to gases and liquids, and also improves its resistance to erosion and abrasion.
• Improved workability: Silica fume can improve the flowability and self-levelling properties of refractory castables. This makes them easier to pour and cast, and also helps to reduce the likelihood of voids and defects in the finished product.
• Increased resistance to high temperatures: Silica fume has a high melting point and is very resistant to thermal shock. This makes it an ideal material for use in refractory castables that will be exposed to high temperatures.

Silica fume is typically added to refractory castables at a level of 5-10% by weight. The exact amount of silica fume required will depend on the specific application and the desired properties of the castable.

Silica fume is used in refractory casting applications

• Furnace linings
• Incinerators
• Kilns
• Reheat furnaces
• Ladle linings
• Tundishes
• Crucibles
• Molten metal handling equipment

Silica fume is a versatile and effective material that can be used to improve the properties of refractory castables in a number of ways. It is a valuable addition to any refractory castable formulation, and is essential for applications where high performance and durability are required.