Description of Casting Sand

Ceramic Sand is a kind of refractory particle with diameter of 0.020mm~3.350mm, mainly 

made of Al2O3·SiO2. It is ball-shaped particle made from bauxite by high-temperature melting 

in electric-arc furnace, spraying and cooling. 

 

Features of Casting Sand

Solid spherical sand

  1) Excellent in fluidity and filling efficiency owing to its ball-shape. For complex shape castings, inner include angle, deep concave, flat holes and other parts which are difficult to fill, it can work efficiently. Thus, the defect like metal penetration and the workload of cleaning can be reduced significantly.

  2) Smooth surface, the structure is tight, and the binder can be uniformly covered.

  3) Small surface area can reduce one third the amount of binder.

High refractoriness

  1) Superior refractory equivalent to zircon and Chromites

  2) Higher than silicon sand, can be used for casting various materials.

  3) Non-stick, non-sintering on the casting, which reduces the deformation of the casting.

Low coefficient of thermal expansion

  1) Can be comparable to the zircon sand.

  2) Ensures fewer or no casting defects such as veining and deformation.

Low gas evolution and high permeability

   Can reduce defects, increase overall yield of casting and lower the cost of casting materials.

Low bulk density

  The bulk density is 1.79-1.87/cm3, lower than the chromite sand of 2.5-2.9/cm3.The sand core is easy to move with light weight, and also can reduce the usage amount of sand.

Artificial foundry sand

  1) It has stable chemical parameter and unified physical properties.

  2) Acid and alkali binder can be used.

Low cleavage breakage rate

   It is not only can be easily reclaimed but also makes it more environment protective from powder dust. Owing to its performance regeneration, cost of material can be reduced tremendously.

 

Applications of Casting Sand

? Widely used in foundry technique like resin-bonded sand, sodium silicate sand, and clay- 

   bonded sand for sand core and casting mould making.

? Replace chromite sand and widely used in sand core making like jacket core, oil duct core, 

   tappet core of engine.

?  Replace chromite sand for steel casting facing sand and sub-layer of molding sand (backing

    sand).

? Widely used as dry sand and sand box for EPC process and V method of casting processes. 

? Widely used as the main raw materials of advanced refractory products (Ladle drainage sand,

     gravity casting material, casting coating, etc.).

?  Widely used as cleaning sand for copper and aluminum alloy castings.

 

Classification of Casting Sand

1. Physical and Chemical Properties

Item	Index	Item	Index(%)
Bulk Density(g/ cm3)	1.79-1.87	Al2O3	65-82
Apparent Porosity(%)	<10	SiO2	15.32-21.6
Ambient Compressive Strength (Mpa)	46	Fe2O3	1.5-3.0
Refractoriness (°C)	≥1800	MgO	0.23-0.7
Refractoriness Under Load (°C)	1720	CaO	0.16-1.5
Thermal Expansion Rate%(800-1450)	0.03-0.13	TiO2	1.99-2.71

2. Grain Size Composition

Model	Mesh	AFS	20 Mesh  and Above	30mesh	40mesh	50mesh	70mesh	100mesh	140mesh	200mesh	270mesh and below
TCS-350#	30/50	25~40	≤10%	≥70%			≤10%	≤3%
TCS-450#	50/30	30~40	≤20%		≥70%				≤5%
TCS-550#	50/30	45-60	≤10%		≥70%				≤10%	≤5%
TCS-650#	70/140	55~70	≤5%			≥15%	≥70%			≤5%
TCS-750#	140/70	70~80	≤10%				≥70%			≤10%	≤6%