Foundry Mullite Casting Sand 30-60mesh Fire Resistant For Investment Casting / Vacuum Suction Casting

1. Mullite Sand Introduction

1. Casting sands are made from mullite.

2. The density of mullite is generally greater than 2.5g/m3, the true specific gravity is 2.6g/cm3, the water content is less than 0.03%, and the fire resistance is greater than 1750 ℃. Under the condition of high temperature burning, its weight will be reduced by 0.3% and not more than 0.4%, which shows the stability of mullite's chemical properties. Its pH value is between 7 and 9, and the hardness of the shell is greater than 8 MPa.

3. The casting sand raw material of mullite is made of kaolin by high temperature sintering. The chemical components of mullite are all chemical substances with strong fire resistance, and their properties are relatively stable. It mainly includes: alumina, silica, etc., the content of alumina is between 42% and 46%, and the content of silica is between 51-53%.

4. 200 Mesh High-alumina Precision Investment Casting Sands with Low Thermal Expansion Coefficient is a series of mullitesand and powder with high aluminum content, low iron content, low coefficient of thermal expansion, high refractoriness and stable thermochemical proprities, which are made of hard clay mineral resources through high-temperature roasting, crushing, screening, Raymond, iron removal and other machining processes.

2. Mullite Sand Specifications

3. Mullite Sand General advantages

Ø Easy out of shell.

Ø No deformation and No reduced scale.

Ø Good brightness and Good finish.

3. Mullite Sand Characteristics

Ø High refractoriness.

Ø Aluminum content high, the iron content low.

Ø High volume density.

Ø Thermal expansion coefficients of small.

Ø Physicochemical stability.

Ø Fully calcined and Dust content low

Ø The specification standards.

4. Mullite Sand Particle sizes Available

Ø Size of sand: 8-16,16-30,30-60,30-80,60-80,80-120 (mesh):Used for investment casting.

Ø Size of powder: -200mesh,-270mesh,-325mesh: Used for investment casting and refractories.

Ø Size of particle: 0-1mm,1-3mm,3-5mm,5-8mm,8-15mm,0-5mm,0-50mm:Used for refractories.

5. Mullite Sand Applications

The precision investment casting sand are mainly used in investment casting,especially in reinforcement layer, gypsum filling V method molding and vacuum suction casting, as well as refractories for large, medium and small steel castings, widely used in machinery, aviation, weapons, metallurgy, petroleum and other industries.

The grain size of mullite is also different for different purposes. Generally, we use "mesh" to measure the grain size of mullite, including 8 to 16 mesh, 16 to 30 mesh, 30 to 60 mesh, 60 to 80 mesh, 80 to 120 mesh; mullite powder mainly includes 200 mesh and 300 mesh.

To make the back layer slurry, 200 mesh mullite and silica sol are needed, and 30-60 mesh mullite is added to the slurry.

Sealing paste, only need to use 200 mesh mullite powder and silica sol.