Aluminate cement characteristics introduction

Aluminate cement is a hydraulic cementitious material made from bauxite and limestone as raw materials, clinker with calcium aluminate as the main component and an alumina content of about 50%, and then ground. Aluminate cement is often yellow or brown, but also gray. The main minerals of aluminate fire cement are monocalcium aluminate (CaO·Al2O3, abbreviated as CA), other aluminates, and a small amount of dicalcium silicate (2CaO·SiO2).

Characteristics of aluminate cement

• Aluminate fire cement sets and hardens quickly.
• The heat of hydration of aluminate cement is large and the heat release is concentrated. Aluminate cement also sets and hardens quickly and can be used for winter construction projects.
• Under ordinary hardening conditions, aluminate cement has strong resistance to sulfate corrosion because the cement stone does not contain tricalcium aluminate and calcium hydroxide and is relatively dense.
• Aluminate cement has high heat resistance. If refractory coarse and fine aggregates (such as chromite, etc.) are used, heat-resistant concrete with a service temperature of 1300 to 1400°C can be made.

What are the characteristics of high-quality refractory cement?

(1) Refractory cement fineness: The finer the cement particles, the larger the specific surface area, the faster and more complete the hydration reaction, and the higher the early and later strength. National regulations: the specific surface area should be greater than 300 square meters per kilogram, otherwise it will be unqualified.

(2) Refractory cement setting time: To ensure sufficient time to complete various processes such as mixing, transportation, and molding during construction, the initial setting time of cement should not be too short; after construction is completed, it is hoped that the cement can harden as soon as possible to produce strength. , so the final setting time should not be too long. The initial setting time of refractory cement shall not be earlier than 45 minutes, and the final setting time shall not be later than 390 minutes.

(3) Volume stability of refractory cement: The uniformity of volume change of cement slurry during the setting and hardening process is called the volume stability of cement. If the volume changes unevenly, the volume stability is poor, which may easily cause warping and cracking, reduce the quality of the project, and even cause accidents.