Partially pyrolyzed composites with basalt fibres – Mechanical properties at laboratory and elevated temperatures

Mechanical properties of partially pyrolyzed at 650 °C or 750 °C unidirectional basalt fibre composites with polysiloxane matrix were studied at laboratory and elevated temperatures. Ten pyrolysis processes differing mutually in heating courses and ultimate temperatures were compared. The material treated at 650 °C revealed at laboratory temperature flexural strength around 850 MPa. Fracture toughness of this material exceeded that of the cured only (at 250 °C) and treated at 750 °C composites. However, the composite pyrolyzed at 750 °C is more suitable for applications at elevated temperatures because of its slower degradation in hot air.