Mechanical properties and microstructure of nano-ZrO₂ reinforced cementitious composites

A series of nano-ZrO₂ reinforced cementitious composites were prepared through mixing prepared nano-ZrO₂ suspension with Class G oil well cement in rotary mixer. The rheological properties of cement slurry, the mechanical properties and microstructure of cementitious composites were studied. The results indicated that the addition of nano-ZrO₂ below 1 wt% meet the requirements of cementing construction. The early compressive strength of cement stone for 1 day was about 35.6 MPa∼41.8 MPa when the amount of nano-ZrO₂ was 0.05 wt%∼1 wt%. The elastic modulus of nano-ZrO₂ cement stone was 8.14 GPa under uniaxial stress state. Microstructure analysis revealed that nano-ZrO₂ could enhance the toughness of cement paste. (paper)