High-Calcium Magnesia Brick   This product is made from high quality magnesite and dolomite as main raw material, and processed by light roasting, fine crushing, pressing briquette, dead burning, pressure moulding, and high temperature firing, possesses very good temperature performance and slag resistance. It can be used for AOD and VOD furnaces, cement kilns, steel refining furnaces and ladles,etc.   Properties   INDEX ITEMS MG-10 MG-15 MG-20 MG-25 MG-30 ω (MgO)/% ≥ Xmin 80 75 70 65 60 79 74 69 64 59 ω (CaO)/% ≥ Xmin 10 15 20 25 30 9 14 19 24 29 ω (Σ S SAF a )/% ≤ 3.0 Xmax 3.3 ≤ 8 App. Porosity/% Xmax 9 ≥ 3.00 2.95 Volume Density Xmin 2.96 2.91 ≥ 50 C.C.Strength Xmin 40 ºC ≥ 1700 0.2MPa Refractoriness under Load 1680 Xmin           Note: The technical parameters in the said table Xmax and Xmin are only applied to decide the retesting conclusion through GB/T 10325-2001. SSAF is the total contents of SiO 2 ,Al 2 O 3 ,Fe 2 O 3 in the products. The supplier and buyer can draw an agreement to adjust the parameter a.