What is ceramic sand?
Ceramic sand, also known as electric fused ceramsite, ceramsite sand, jewelry sand, and its scientific name 'molten ceramic sand', has the advantages of high temperature resistance, no crushing, no dust, spherical shape, high permeability, good filling performance, and no harm of silicon dust. It is a green casting sand for environmental protection.
Quartz sand has the advantages of wide distribution and low cost; But its shortcomings are also quite obvious: first, the expansion coefficient is large and the casting precision is low; Second, the surface of the casting is seriously bonded with sand, and it is difficult to remove the sand. The reason is that there are many kinds of homogeneous and heterogeneous crystals in quartz at different temperatures, and the volume changes greatly; Due to the limitation of fire resistance (the fire resistance of quartz sand is between 1400 -1700 ℃), local parts of the casting (holes, grooves, and hot spots) have serious sand sticking, which is very difficult to clean. These shortcomings are particularly serious in the production of large steel castings.
Characteristics and application of ceramic sand
Ceramic sand can overcome these shortcomings and greatly improve the quality of castings.
Ceramic sand is made from high-quality bauxite through calcination, electrofusion, granulation, screening and other processes.
. The thermal expansion coefficient is small, and its performance is comparable to that of zircon sand. When it is used to prepare molding sand, the castings will not have expansion defects;
. The sand is spherical, with good fluidity, easy compaction and good air permeability
. The surface is smooth and the structure is dense, so that the adhesive can be evenly covered
. Ceramic sand is a neutral material, which can be used as acid or alkali binder
. Good recycling performance and high cost performance
Compared with chromite sand and zircon sand, its price is only 25-50% of zircon sand and chromite sand. At the same time, because the sand is spherical and its surface area is small, the addition amount of resin can be reduced by 30-50%, and the addition amount of water glass ≤ 4%; The casting defects caused by binder are reduced and the yield of castings is improved
. High fire resistance, easy to collapse
The mullite phase of ceramic sand is much higher than that of sintered products and has good fire resistance
. High thermal conductivity, good stability and no cracking
. Wide application range
Sodium silicate sand, resin sand, precision casting and polishing and cleaning of copper and aluminum parts