Abstract:

The chemical composition, X-ray diffraction, thermal properties, flammability, mechanical properties and morphology of basalt fibres are investigated in this paper. Chemical analysis and energy dispersive X-ray fluorescence spectrometer experiments showed that basalt fibre is a kind of aluminosillicate fibre which is mainly composed of oxides such as SiO2, Al2O3, Fe2O3, CaO, MgO, Na2O, K2O, P2O5 and so on. X-ray diffraction indicated that the bulk structure of the fibres is non-crystal with a short range order but no long range order. SEM observation found that basalt fibre is circular in cross-section and smooth in the longitudinal direction. Solubility experiments revealed the superior resistance of the fibre to acids, alkaline and organic solvents. DGA demonstrated there are three weight loss stages in the process of elevating temperature. They are, respectively, evaporation of moisture in the fibre at about 100 °C, decomposition of the residual carbonate minerals between 480 °C and 630 °C, and decomposition of newly generated carbonates between 850~995 °C. On the heat flow curve, there are also three endothermic peaks, where the first and second correspond to the last two stages of weight loss and the third to the melting process of the fibre, whose onset is from 1122.14 °C, reaching a peak value at 1194.96 °C, and ending at 1380 °C. The tensile strength of basalt filaments and staple fibre was measured. Tensile and shear properties of the fibre were also tested.