Ceramic sand (also known as molten ceramic sand, pearl sand) is widely used in the field of steel casting due to its excellent refractory properties, low thermal expansion, spherical particle characteristics and environmental advantages. The following are its main applications and technical features in the field of steel casting:
1. Sand core and molding sand materials for steel castings
Ceramic sand can effectively reduce defects such as sand inclusion, scarring, and pores in steel castings during the pouring process due to its high refractoriness (1800~2000℃) and extremely low thermal expansion rate (0.13% @1000℃)4.
Application case: Weichai Power uses ceramic sand and roasted sand to replace chromite sand to produce high-speed engine cylinder water cavity sand cores. The inner cavity sand adhesion defect is reduced from 0.6% to below 0.2%, and the material cost is reduced by 15%4.
Advantages:
High disintegrability: The resin sand core is easy to clean after pouring, reducing the workload of sand cleaning1.
Low gas emission: Reduce the pore defects of steel castings and improve the yield rate5.
2. Resin self-hardening sand process for large steel castings
In the production of large steel castings, ceramic sand is used as the raw sand for resin self-hardening sand, which can reduce the amount of resin (reduced by more than 30%), while improving the strength of the sand mold, reducing the amount of gas generation, and improving the disintegration15.
Compared with traditional silica sand:
Silica sand has a high thermal expansion rate, which can easily lead to dimensional deviation of castings; ceramic sand has almost no expansion, and the casting precision is higher4.
Silica sand is difficult to regenerate, and ceramic sand can be recycled many times to reduce waste sand emissions1.
3. High alloy steel and heat-resistant steel casting
The high aluminum content of ceramic sand (Al₂O₃≥75%) makes it suitable for high alloy steel (such as heat-resistant steel, stainless steel) casting, reducing the risk of chemical sand sticking4.
Case:
The surface quality of stainless steel castings produced by the ceramic sand coated sand shell mold process is close to the level of investment casting, while shortening the production cycle8.
In the production of high-temperature resistant steel castings (such as ZG10Cr9Mo1VNbN), ceramic sand can withstand high temperatures of 620°C5.
4. Environmental protection and cost advantages
Reduce dust pollution: Ceramic sand particles are dense and have a low crushing rate, which reduces the harm of silica dust in the foundry workshop1.
Challenges in recycling old sand: At present, it is difficult to separate ceramic sand from molding sand after mixing, and the recovery rate is low, and the regeneration technology needs to be further optimized47.
5. Future development trends
3D printing sand regeneration technology: For example, the 3D printing sand regeneration system of Lianxin Group can restore 95% of the performance of old sand and reduce sand consumption by 40%. It may be used in ceramic sand regeneration in the future7.
Growth in the Asia-Pacific market: Driven by the automotive and rail transportation industries, the application of ceramic sand in the field of steel casting is expected to grow at an annual rate of 6% (2024-2029
