摘要 |
<p>An artificial lightweight aggregate comprising SiO2, A l 2O3, Fe2O3 and at least one oxide selected from the group consisting of MgO and CaO, in which the total amount of SiO2 and A l 2O3 ranges from 75 to 92 wt.%, a weight ratio of A l 2O3/SiO2 ranges from 0.25 to 0.70, and the total amount of Fe2O3 and MgO and/or CaO ranges from 6-20 wt. %, which has an absolute dry specific gravity of not higher than 1.50, a crushing strength of not less than 55 kgf/cm<2> and a 24 hour water-absorption ratio of not greater than 2.4%. </p> |