Influence of the specific area of quartz sand on the character of an autoclaved calcium silicate composite

Influence of the specific area of quartz sand on the character of an autoclaved calcium silicate composite

WoS Article

The physical-mechanical properties of calcium silicate composites are structure dependent. It is necessary to check the properties of the raw materials to ensure the required quality of the calcium hydro silicate microstructure. One of the decisive features is the specific surface area of the siliceous material. The particle size significantly affects the solubility during autoclaving and thus incorporating the silica into the microstructure. This paper deals with the influence of the particle size of quartz sand on the properties and structure of the composite. Two types of sand were used with three different specific surfaces. The tested values of the specific surface area of the quartz sand were 1300 cm2/g, 2600 cm2/g and 3600 cm2/g. The sand was mixed with lime in molar ratios of calcium oxide to silicon dioxide equal to 0.73 and 1.00. The calcium silicate composites were exposed to a hydrothermal treatment at 190 °C for an isothermal endurance time of (4, 8 and 16) h. The mechanical properties were determined for the treated samples. The samples were further studied by microstructure, by X-ray diffraction analysis and by scanning electron microscopy.

The physical-mechanical properties of calcium silicate composites are structure dependent. It is necessary to check the properties of the raw materials to ensure the required quality of the calcium hydro silicate microstructure. One of the decisive features is the specific surface area of the siliceous material. The particle size significantly affects the solubility during autoclaving and thus incorporating the silica into the microstructure. This paper deals with the influence of the particle size of quartz sand on the properties and structure of the composite. Two types of sand were used with three different specific surfaces. The tested values of the specific surface area of the quartz sand were 1300 cm2/g, 2600 cm2/g and 3600 cm2/g. The sand was mixed with lime in molar ratios of calcium oxide to silicon dioxide equal to 0.73 and 1.00. The calcium silicate composites were exposed to a hydrothermal treatment at 190 °C for an isothermal endurance time of (4, 8 and 16) h. The mechanical properties were determined for the treated samples. The samples were further studied by microstructure, by X-ray diffraction analysis and by scanning electron microscopy.

quartz sand, specific surface, tobermorite, calcium-silicate composite

quartz sand, specific surface, tobermorite, calcium-silicate composite

HÚŠŤAVOVÁ, J.; ČERNÝ, V.; DROCHYTKA, R.

2019

01.02.2019

Inštitut za kovinske materiale in technologije

Ljubljana

1580-2949

Materiali in Tehnologije

53

1

Republic of Slovenia

39

47

9