• Home
  • Company
  • What is Calucem?
  • Sales Offices
  • Quality Control
  • Products
  • Compare Products
  • HiPerCem®
  • ISTRA Types
  • ISTRA 40
  • ISTRA 45
  • ISTRA 50
  • Packaging
  • REFCON® plus
  • Packaging
  • Special Products
  • REFCON® plus
  • Packaging
  • Applications
  • Building Chemistry
  • Construction Industry
  • Pipes & Aggregates
  • Refractory Industry
  • Reprocessing
  • Case Studies
  • Sample Order
  • News & Events
  • Overview
  • Contact
  • Mailform
  • Sales Offices
  • Africa/Middle East
  • Asia/Pacific
  • Europe
  • North America
  • South & Latin America
  • Procurement
  • Cemfast

    CEMFAST is an anthracite-brown, quick-setting and fast-hardening Calcium Aluminate Cement with high early strength values. This special performance is facilitated by matched mineralogy in connection with optimum granulometry. This offers clear advantages, particularly in the early phase of the setting process.

    The compressive strength after 6 hours is up to 10% higher than with classic Istra 40 – without having to accept serious trade-offs during the remaining hardening process.

    CEMFAST is therefore ideally suited to all applications in which the strength at the start of the setting process needs to be improved without compromising the final strength value. CEMFAST is also suitable for use with ternary binder systems with the objective of achieving fast ettringite formation.

    Typical fields of application include fast, technically challenging systems:

    • quick repair mortars
    • repair systems for road construction applications
    • anchor mortar for mining applications.

    CEMFAST fulfills the requirements of EN 14647. 

    CEMFAST is part of a product range for specific applications in the field of construction chemistry. The following comparison provides an initial overview of the key properties of these aluminate cements for special applications.

    Setting Early Strength
    ISTRA 40 + +
    CEMFAST ++ ++
    CEMFAST RS +++ +
    BRICOCEM ++++ +


    CEMFAST is produced by melting selected raw materials (bauxite and limestone) in special kilns. After cooling, the clinker is ground using ball mills.

    Technical data

    The following information represents typical values for the quality control carried out in our plant.

    Mineralogical composition

    CEMFAST contains mainly monocalcium aluminate (CA). This mineral phase is responsible for the high early strength. When mixed with water CEMFAST forms calcium aluminate hydrates as its hydration products.

    Mineral phases of CEMFAST

    main mineral phase: CA
    minor mineral phases: C4AF, C2AS, C12A7

    Chemical composition (%)

    SiO2 ≤ 6
    Al2O3 37–42
    Fe2O3 12–17
    CaO 37–42
    MgO < 1,5
    SO3 < 0,4

    Cement technical properties

    residue on sieve at: 90 mm < 3%
    fineness (Blaine) approx.: 3700–4300 cm²/g
    bulk density approx.: 1.15 g/cm³
    specific gravity: 3.2–3.3 g/cm³
    refractoriness in cement approx.: 1270 °C

    Setting time and water demand

    The testing of the setting time is performed using the mortar in order to describe the behaviour of the CEMFAST in mixtures with a workable consistency. A mixture containing CEN-standard sand and using a water/cement ratio of 0.40 is produced for testing the mortar on the basis of EN 14647.

    Initial set 0:30–2:30 h
    Final set maximum 120 min after initial set
    Water demand 26 ± 2%

    Resistance to corrosion

    High resistance to waste waters in combination with extraordinary abrasion resistance and high resistance to biogenic sulphuric acid corrosion (BSAC) makes CEMFAST an ideal product for sewer systems and waste water plants. When CEMFAST is mixed with water, the hydration products of calcium aluminate are formed. They are extremely resistant to aggressive, slightly acid waters (pH factor > 3) including water soluble sulphates.


    After drying out, mortars and concretes made from CEMFAST slowly emit their hydrate water without destroying the matrix. At high temperatures (> 1000 °C), ceramic bonding occurs between the high alumina cement parts and the refractory aggregates. These ceramic bonds make CEMFAST an excellent binder in refractory concretes and other refractory mortars or gunning mixes.


    Like all other Calucem products, the production of CEMFAST is subject to stringent quality control. Constant monitoring of all components ensure a consistent quality. The production plant is certified according to EN ISO 9001 – certificate number CH08/1542 and the Environmental Management System EN ISO 14001 – certificate number CH08/1543.

    Safety instructions

    The normal safety measures for cement must be followed. You will find further information in our safety data sheet.