Investment Casting Grade

2.1

SiO₂

>99.90%

2.2

Al₂O₃

<200ppm

The finer the power,the higher the Al2O3,as powder is produced by ball mill with Alumina ball.

2.3

Fe₂O₃

<50ppm

2.4

TiO₂

<20ppm

2.5

MgO

<40ppm

2.6

CaO

<40ppm

2.7

Alkalies
Na₂O+K₂O

<100ppm