چكيده به لاتين
Calcium aluminate and strontium aluminate cements can be used in refractory, tooth filling, catalytic, etc. applications. In this research, the study of combustion synthesis of 3CaO∙Al_2 O_3 (C_3 A), 12CaO∙7Al_2 O_3 (C_12 A_7), 3SrO∙Al_2 O_3 (Sr_3 A) phases and their physical and mineral properties were investigated. , obtained controllable properties in terms of phase, time, etc. For this purpose, at first calcium nitrate precursors, company, strontium and urea fuel were dissolved in water in stoichiometric ratio and after gelation, combustion was done at oC 500. X-ray diffraction results indicated that C_3 A and C_12 A_7 phases were not formed with the above fuel, but a small amount of Sr_3 A phase in the combustion gel sample was related to the formation. By taking the simultaneous thermal analysis of the samples, calcination at 90°C is selected to reach the desired phases, which is confirmed by the X-ray diffraction pattern. C_3 A and C_12 A_7 cement paste alone and together with Sr_3 A 20% by weight in a binary system and a ternary system containing 60% by weight C_3A, 20% by weight C_12A_7, 20% by weight Sr_3A with suitable water ratios of 0.39 which Their final setting time was 30-110 minutes and after seven days it contained C_3 AH_6, Sr_3 AH_6 and AH_3 hydrated phases along with amorphous phases, which were generally hydrated phases below 5 μm and mostly in the form of plates, hexagonal, edged rods. They became needles. FTIR analysis of different samples indicates that there is also the possibility of carbonate phases in hydrated phases.
