The Comparison of Brown Fused Alumina And Garnet in Rust Removal of Stainless Steel Surface

- Nov 14, 2018-

The Comparison of Brown Fused Alumina And Garnet in Rust Removal of Stainless Steel Surface

In stainless steel blasting, the choice of proper abrasive grain can save resources, reduce production costs, and increase production efficiency. Brown fused alumina and garnet are usually used. The brown fused alumina is made of bauxite and auxiliary materials in the electric arc furnace and is smelted at a temperature higher than 2,000℃. The hardness of the first grade product is usually greater than 9 Mohs grade and the alumina content is over 95%. Garnet is a natural abrasive, mainly composed of iron-aluminum garnet (mainly containing iron-aluminum silicate crystal), and the hardness is generally not more than 7 Mohs.

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                              Garnet

brown fused alumina

                   Brown Fused Alumina 

Comparison of garnet and brown fused alumina abrasive technical indicators

Index 

Garnet

Brown Fused Alumina

Main Chemical

Fe3Al2(Sio4)3

95% Al2O3

Hardness

7.5

9

Melting Point

1250

2250

Specific Gravity

3.7

3.9

PH

7.0

6.5

The differences of Brown fused alumina and garnet in blasting process are listed below.

(1) As the particle size of the brown fused alumina abrasive is reduced, the surface roughness of the stainless steel is also reduced, but the cleanliness of the stainless steel surface is gradually improved.

(2) Compared with brown fused alumina, garnet has a congenital deficiency, so it is not as good as brown fused alumina abrasive in sandblasting efficiency and break rate.

(3) There is a general problem of sand embedding in garnet sandblasting. Although the selection of small-size abrasives can solve the sand-embedding, the roughness of the punching is difficult to reach the requirement of 40~75um, and the brown fused alumina abrasive 22 mesh can satisfy the roughness requirements.

(4) The surface of  steel is brighter after garnet blasting and more beautiful, and it is more acceptable in cleanliness.

(5) In comparison, the garnet generate more dust that brown fused alumina during the blasting process which will do harm for the workers. 

Considering the cost, technical requirements, sandblasting efficiency and other factors, brown fused alumina abrasive is more suitable for stainless steel surface treatment.