Magnesium Aluminate Spinels

Magnesium Aluminate Spinels are recognized as a superior refractory aggregate for providing high slag corrosion resistance and thermal shock resistance to refractory products. The Almatis Magnesium Aluminate Spinel product line includes both alumina-rich and magnesia-rich spinels: magnesia-rich spinel product for use with magnesia-based refractories and alumina-rich spinel for use with alumina refractories.

Magnesium Aluminate Spinel Applications

Almatis’ magnesia-rich spinel replaces chrome ore in basic refractories especially bricks for cement rotary kilns. It imparts the improved thermal shock resistance normally associated with chrome additions, but without the potential problem of hazardous waste disposal. Also, the free magnesia in Almatis magnesia-rich spinel MR 66 serves as a setting agent for phosphate bond to produce a cold setting monolithic refractory or mortar.

Almatis alumina-rich spinels AR 78 and AR 90 are used in alumina refractories, e.g. for steel ladle applications. AR 78 and AR 90 are distinguished by their chemistries (78% and 90% alumina respectively). Alumina-rich spinel addition to alumina shapes and monolithics improves their slag resistance and thermal shock resistance. Also, the thermo-mechanical strength, for example the hot modulus of rupture, can be increased considerably.

Benefits of Almatis Magnesium Aluminate Spinels

  • High quality pre-reacted spinels ensure volume stability during firing
  • Stable at very high temperature (melting point 2135°C [3875°F])
  • High chemical and thermal shock resistance
  • Improves resistance to slag attack
  • Magnesia-rich spinel replaces chrome ore
  • Alumina-rich spinel improves the thermomechanical strength of high alumina refractories

Why Almatis Magnesium Aluminate Spinels are Premium

  • Full product range of both alumina and magnesia-rich spinels
  • Manufactured from high purity raw materials
  • Very homogenous, pure products for producing high quality refractories
  • Available in a wide variety of crushed and milled sizes to optimize refractory formulations
  • Global product specifications deliver the same product around the globe
  • Short lead times available in all world regions

Almatis Magnesium Aluminate Spinels

The Almatis Magnesium Aluminate Spinel product line includes both alumina-rich and magnesia-rich spinels.

AR 78 Alumina- rich spinel (78% alumina by weight), for steel ladle shapes and monolithics
AR 90 More Alumina-rich spinel (90% alumina by weight), also for steel ladle refractories
MR 66 Magnesia-rich for use in MgO-containing refractories, where chrome replacement is needed