The application of chromite sand flour in precision casting and casting coating
The application of chromite sand flour in precision casting and casting coating is mainly reflected in the following aspects:
Application in precision casting
In precision casting, the commonly used are chromite sand AFS40-45 AFS45-50 AFS45-55 and chromite flour 200 mesh
Preventing sand from sticking to the surface of castings: Chromite sand flour is mainly used for the surface sand of large steel castings in precision casting. When in contact with molten metal, chromiite sand flour itself has the characteristics of solid phase sintering, which can effectively prevent the penetration of molten metal, thereby preventing sand from sticking to the surface of castings, maintaining the surface finish of steel castings, and improving the quality of castings.
Acting as a chilling material: The thermal conductivity of chromite sand flour is several times greater than that of silica sand. It can be used as a chilling material to replace part of the cold iron, accelerate the cooling rate of castings, and prevent casting defects such as cracks and pores. It is particularly suitable for the production of high-precision and high-performance castings
Applied in a variety of casting processes：Chromite sand flour is suitable for a variety of casting processes, such as sand casting, lost foam casting, shell casting, etc. In lost foam casting, the selection of chromite sand flour with appropriate particle size can prevent defects such as sand inclusion and sand sticking caused by quartz sand casting; in shell casting, chromite sand flour is used as the core sand material of complex parts to effectively prevent the problem of sand sticking in the inner cavity of the casting.
Application in casting coatings
Here, casting coatings mainly refer to cast steel coatings and cast iron coatings, and chromite flour 200 mesh 325 mesh is commonly used.
Improve refractory performance: After chromite sand is ground into powder, it can be added to casting coatings as refractory aggregate to significantly improve the refractory performance of the coating. Its refractoriness is as high as 1900°C, which can keep the coating from burning, softening and falling off at high temperatures, ensuring the integrity of the mold and core.
Enhance the physical and chemical properties of the coating: The addition of chromite flour can enhance the hardness, wear resistance and corrosion resistance of the coating, improve the hardness and wear resistance of the casting surface, and extend the service life of the casting. In addition, chromite sand flour can also participate in the reaction to form a hard protective layer, effectively avoiding oxidation and corrosion of the metal surface.
Reduce coating manufacturing costs: Compared with other fillers, chromium ore powder has higher hardness and melting point, can maintain excellent physical and chemical properties at high temperatures, and is suitable for a variety of different casting coating formulations. In addition, the particle size and addition amount of chromite sand flour can be adjusted according to specific needs to achieve more refined coating formulations and higher coating performance requirements.
In summary, the application of chromite sand flour in precision casting and casting coatings not only improves the quality and performance of castings, but also reduces production costs, and has broad application prospects.
