Microsilica 955

Elkem Microsilica® 955 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
  • Gelification (coagulation) in gunning mixes
  • 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 955 is offered both as Undensified (955-U) and Densified (955-D)

Chemical Analysis (weight %)
ElementUnitSpec
 SiO2  % min  95.5
 Cfree **   % max  1.0
 Fe2O3  % max  0.3
 Al2O3  % max  1.0
 CaO  % max  0.4
 MgO  % max  0.5
 K2O  % max  1.0
 Na2O  % max  0.4
 H2O *  % max  1.0

Physical data
PropertiesUnitSpec
Loss on Ignition   % max  2.0
Coarse particles >45µm  % max 1.0 
pH-value    6.5 - 8.5
Bulk density undensified 955-U * kg/m3  260 - 380 
Bulk density densified 955-D * kg/m3 450 - 650 

* When packed
** C in SiC is not included

Test methods

Test methods are available upon request