High Alumina Cement The index of Alumina cement Aluminate cement CA40-Fused CA50-J5 CA50-J6 CA50-J7 CA50-N CA50-J9 CA50-Fused Blaine (cm2/g) =2700 =3000 =3000 =3000 =3000 =4000 =4000 Initial time(h:m) =0:40 =0:30 =0:30 =0:30 =0:30 =1:30 =2:00 Final time(h:m) =4:00 =6:00 =6:00 =6:00 =6:00 =6:00 =6:00 Flexural strength(Mpa) 6hrs=4.0 =4.0 1 day =5.5 =5.5 =6.0 =6.5 =6.0 =8.0 =10.0 3 days =6.5 =6.5 =7.0 =7.5 =7.0 =10.0 =11.0 Compressive strength 6hrs=30.0 =35.0 1 day =50.0 =40.0 =45.0 =50.0 =50.0 =70.0 =75.0 3 days =60.0 =50.0 =55.0 =60.0 =60.0 =80.0 =85.0 Chemical composition SiO2 % =6.0 =8.0 =8.0 =8.0 =6.5 =6.0 =5.0 Al2O3 % =37.0 =50.0 =50.0 =51.0 =50.0 =53.0 =50.0 CaO % =38.0 =33.0 =33.0 =33.0 =33.0 =33.5 =38.0 MgO % =1.5 =1.5 =1.5 =1.5 =1.5 =1.5 =1.5 TiO2 % =3.0 =3.0 =3.0 =3.0 =3.0 =3.0 =3.0 Fe2O3 % =18.0 =3.0 =3.0 =2.5 =3.0 =2.5 =50.0