Microsilica 971

Elkem Microsilica® 971 is a key ingredient in low and ultra-low cement castables. It is highly reactive during sintering, which leads to improved ceramic bonding at reduced firing temperatures. The grade is used in mortars, gunning mixes and other shaped and unshaped materials.

General

  • Improved flow – easier to cast
  • Improved particle packing - denser castables
  • Gel-bonding
  • Improved hot-strength properties 

Application

  • Low and ultra-low cement castables
  • Castables, mortars, gunning mixes and other shaped and unshaped materials. 

Packing

The product is available in 25 kg small bags and various sizes big bags. Please contact our sales representative for more details. 

Storage conditions

Store in the original packaging (or re-seal opened packages) under dry conditions above 0°C.

Elkem Microsilica® Grade 971 is offered both as Undensified (971-U) and Densified (971-D)

Chemical Analysis (weight %)
ElementUnitSpecTypical *
SiO2 % min 98 98.4
Cfree ** % max 0.7 0.5
Fe2O3 % max 0.1 0.01
Al2O3 % max 0.3 0.2
CaO % max 0.3 0.2
MgO % max 0.2 0.1
K2O % max 0.3 0.2
Na2O % max 0.2 0.15
P2O5 % max 0.1 0.03
SO3 % max 0.3 0.1
Cl % max 0.1 0.01
H2O ***  % max 0.5 0.2

 

Physical data
PropertiesUnitSpecTypical*
Loss on Ignition   % max  0.8 0.5
Coarse particles >45µm  % max 0.5  0.2
pH-value    5.5 - 7.5 6.8
Bulk density undensified 971-U *** kg/m3  250 - 350  300
Bulk density densified 971-D ***  kg/m3 450 - 550  500

* Typical values are for guidance only

** C in SiC is not included

*** When packed

Test methods

Test methods are available upon request