As a casting process with little or no cutting, it is an excellent process technology in the casting industry. Silica gel melt precision casting is widely used. It is not only suitable for casting of various types and alloys, but also produces castings with higher dimensional accuracy and surface quality than other casting methods, and even complex, high temperature resistant and difficult to process castings that are difficult to be cast by other casting methods.
The so-called Silica Sol precision casting process is simply to make a fusible model with fusible materials, coat it with several layers of special fire-resistant coatings, dry and harden it to form an integral mold shell, then melt the model from the mold shell with steam or hot water, then place the mold shell in a sand box, fill dry sand around it for modeling, and then put the mold into a roasting furnace for high-temperature roasting. After roasting, the mold or mold shell, A casting is obtained by pouring molten metal therein.
Silica sol has many excellent characteristics, such as large specific surface area, high adsorption and adhesion, heat resistance and insulation at high temperature, catalytic activity and so on. Thus, it has become an increasingly attractive fine chemical product with broad application prospects.
Coating silica sol containing refractory powder on the surface of the mold can reduce the friction between the mold and the spindle, protect the mold and improve the yield; Especially in precision casting, the ceramic thin shell precision casting method is booming because of the use of silica sol; Using silica sol instead of silicate ester can reduce the cost and improve the operating conditions. The thin shell made of silica sol with small particle diameter has high strength and good finish, which can greatly improve the quality of castings.