Why is silica sol used in investment casting?
Silica sol is a kind of emulsion colloid. Because the colloidal particles are tiny (10-20 microns) and have a large surface area, it does not affect the true color of the coating material. Silica sol is miscible with water and immiscible with organic solvents. Soluble in alcohol or water mixed in any proportion. The salient feature of silica sol is its low viscosity and the ability to soak water, so silica sol exhibits excellent dispersibility and permeability when mixed with other substances. When the water in the silica sol evaporates, the colloidal particles firmly adhere to the surface of the material, and then a combination of silicon and oxygen is formed between the particles. It's a great adhesive. This is the main role of silica sol as a stainless steel molding glue.
Silica sol castings are mainly used for products with high corrosion resistance and high dimensional accuracy, because the surface quality of silica sol steel castings is much better and the dimensional geometric deviation is small. The main silica sol steel castings we manufacture include meat grinder parts, valve castings, pump castings, marine hardware, furniture decoration, etc.
Silica sol casting and water glass casting
Silica sol investment castings have better size and surface quality, but are more expensive than water glass castings. The cost of sol casting is almost twice that of water glass casting. Both silica sol casting and water glass casting belong to investment casting or lost wax casting. So the silica sol casting process is almost the same as the water glass casting process. The silica sol investment casting process uses silica sol zircon sand as the molding material, and the temperature resistance can reach 2000 degrees.