This information is based on our present state of knowledge and is intended to provide general notes on our products and their uses. It should not be construed as guaranteeing specific properties or suitability for a particular application
Calumex® SC-A is an Amorphous Calcium Aluminate (C12A7) additive to Ordinary Portland cement, used to accelerate setting times, compensate shrinkage, and increase both early and late strength development. Calumex® SC-A is the most reactive accelerator for Portland cement systems. At a 10% replacement of OPC, setting times can be reduced from several hours to less than 1 minute.
The specialized chemistry of Calumex® SC-A allows the formulation of ultra-fast setting formulations with extremely high early strengths at early stages of hydration. Furthermore, through the high formation of ettringite crystals, drying is accelerated, and shrinkage and permeability are reduced.
Calumex® SC-A is based on an amorphous clinker, making it much more reactive than crystalline alternatives. This means the required dosage in end formulations can be significantly lower, with between 5-20% of the binder weight replaced by Calumex® SC-A, depending on the desired effect.
| Component | Value |
|---|---|
| SiO2 | ≤ 3% |
| Al2O3 | 20 – 25% |
| Fe2O3 | ≤ 0.5% |
| CaO | 40 – 45% |
| SO3 | ≤ 30% |
| TiO2 | ≤ 1% |
| MgO | ≤ 1% |
| Property | Value |
|---|---|
| Temperature Development | ≥ 50°C |
| Time Achieved | ≤ 10:00 min |
| Appearance | White powder |
| Blaine | ~6000 cm²/g |
| Bulk Density | ~2.9 – 3.1 g/cm³ |
| Age | Calumex® SC-A | Calumex® XT-20 |
|---|---|---|
| 6 hours | ≥ 8.5 MPa | ~12 MPa |
| 24 hours | ≥ 38 MPa | ~45 MPa |
| 72 hours | ≥ 48 MPa | ~60 MPa |
