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Types of Cement

MDF Cement

If any cement innovation has churned up interest in the last few years, it's the the development of "Macro-Defect-Free" (MDF) cement. Defect-Free” refers to the absence of relatively large voids or defects that are normally present in conventional cement pastes because of entrapped air or inadequate mixing.

In the MDF process, water-soluble polymers (4-7%) are added to help keep the cement pliable, thereby requiring less water during mixing. Entrapped air is removed by application of modest pressure.

MDF cements have high compressive strengths, and their flexural properties are remarkable. Cement is notoriously weak under bending. Strength of up to 300 MPa for calcium aluminate system & 150 MPa for Portland cement can be achieved.

Scientists envision all sorts of MDF applications including relatively flexible pipes and fittings, window and door frames and table tops. Turntables, stereo cabinets, bottle caps and springs have been made out of MDF cement. By adding metallic fibers, a material good for isolating electronic equipment from electromagnetic interference (such as might occur during blasts or nuclear tests) can be obtained.