High hardness, big density, low wear lost, good nomalization, good corrosion-resistance. The products are featured by high hardness, big density, low wear lost, good nomalization, good corrosion-resistanceetc. 1. Chemical Composition Al2O3SiO2Fe2O3CaOMgOT:O2Na2OHL-50≥ 50≥ 47≤ 1.0≤ 0.5≤ 0.5 ≤ 1HL-70≥ 70≥ 23≤ 0.8≤ 1≤ 1 ≤ 1.0HL-80≥ 80≥ 16≤ 0.5≤ 0.5≤ 0.5 ≤ 1HL-90≥ 90≥ 6≤ 0.1≤ 0.5≤ 0.5 0.5HL-99≥ 99.2≤ ...