Lost Foam Casting (LFC) is widely used in foundry industry for its advantages of good modeling, good operation and high precision.However, there are still some difficult problems in casting technology and casting quality if only the casting technology is changed and the sand use habit is not changed. Ceramic foundry sand has been introduced into the field of lost foam casting and successfully applied, so that the above problems can be solved.

                                                                                          
 
The biggest advantage of ceramic foundry sand in EPC is that it can be recycled and reused. As we all know, the long-term use of sand temperature is 1800 degrees, good stability, so ceramic foundry sand can be completely renewable, re-use after being used in EPC.
 
In the process of lost foam casting, the sand filler does not use the binder, only need to vacuum in the sand box to ensure the strength of the ceramic foundry sand. Therefore, the cost of ceramic foundry sand as casting sand or filling sand is quite low.The used ceramic foundry sand basically does not need to be treated too much, can be used repeatedly, and has high recycling value, which greatly reduces the use cost of casting sand.
 
According to statistics, the highest recovery rate of ceramic foundry sand can reach 98%;With such a high recovery rate, a investment to buy sand, lasting use, cycle benefit, of course,it is the best choice for casting sand.
 
In the lost foam casting process, the molding sand is usually ceramic foundry sand; Its advantage is that the ceramic foundry sand is spherical particles, good liquidity, strong permeability, and good permeability, which is conducive to the production of high-precision castings. With low coefficient of thermal expansion, the properties of ceramic foundry sand are comparable to zircon sand; With its preparation of molding sand, castings will not produce expansion defects.Its surface is smooth and its structure is dense, so that the adhesive can cover uniformly.

Main Properties of Ceramic Foundry Sand

Main Chemical Composition：AL₂O₃: 68%-75%  SiO₂: 18%-22%  Fe₂O₃≤3%   K₂O≤0.5%  TiO₂≤3%

Physical properties

1. Particle shape：Sphere
 

2. Angle factor: ≤1.1
 

3. Bulk specific weight：1.95-2.05g/cm3
 

4. PH：7-8
 

5.Thermal Conductivity :0.5-0.6(W/m*K)(1000℃)
 

6. Thermal Expansion Rate：0.13%(10 minutes under 1000℃)
 

7. Refractoriness：>1800℃
 

8. Acid Consumption：1.5ml

Ceramic foundry sand is a neutral material, acid, alkali adhesive can be used. Ceramic foundry sand has good recycling and high cost performance; Compared with chromite sand and zircon sand, its price is only 30-50% of chromite sand and  zircon sand; Because the sand particles are spherical and the surface area is small, the amount of resin can be reduced by 30-50%, and the amount of water glass is less than 4%; The casting defects caused by the binder are reduced and the rate of finished castings is increased.The surface of the ceramic foundry sand is smooth and the structure is compact, so that the adhesive can cover uniformly; It has high refractoriness, easy to collapse, high thermal conductivity, high stability and no cracking, thus reducing casting defects and greatly improving the rate of finished castings.