Ceramic sand (also known as spherical sand) is a high-performance casting sand widely used in precision casting and high-end casting production. Its main advantages in casting include:
1. High refractoriness
The main component of ceramic sand is alumina (Al₂O₃), and its refractoriness can reach above 1800℃, which is much higher than ordinary silica sand (about 1710℃). It is not easy to sinter or react with molten metal at high temperature, which can effectively reduce the sand sticking defects on the surface of castings, and is especially suitable for casting of high melting point alloys (such as stainless steel and high temperature alloys).
2. Low thermal expansion coefficient
The thermal expansion coefficient of ceramic sand is only 1/5~1/10 of that of silica sand, and the volume change is very small when heated. This feature can significantly reduce casting defects (such as veins, burrs, deformation) caused by sand mold expansion, and improve the dimensional accuracy and surface finish of castings.
3. Excellent fluidity
Ceramic sand particles are spherical or nearly spherical, with a smooth surface and excellent fluidity. This makes the sand mold filling more uniform, especially suitable for the modeling of complex thin-walled castings, while reducing equipment wear and improving production efficiency.
4. Excellent regeneration performance
Ceramic sand has stable chemical properties and can be recycled multiple times (recycling rate is as high as 90% or more), significantly reducing waste sand emissions and raw material costs. Its durability is better than silica sand and chromite sand, and its long-term economic efficiency is outstanding.
5. Strong chemical inertness
It does not react with molten metal (especially alkaline metals or alloys), avoiding defects such as pores and sand inclusions. At the same time, its low gas emission reduces the risk of gas defects during casting.
6. Wide range of applications
It is suitable for almost all casting processes (such as lost foam, V method, resin sand, etc.) and alloy types (cast iron, cast steel, copper alloy, aluminum alloy, etc.), especially in the fields with high precision and high surface quality requirements (such as automobiles, aerospace).
7. Environmental advantages
There is almost no dust pollution during the regeneration process, and there is no need to add too much binder, reducing harmful gas emissions, which is in line with the development trend of green casting.
Summary
Ceramic sand has significant advantages in improving casting quality, reducing production costs and promoting environmental protection through its high refractory, low expansion and excellent regeneration performance. It is an ideal choice to replace traditional foundry sand, especially suitable for high-end precision casting.
