Note: Rayon-based carbon fibres have a more isotropic structure than similarly heat-treated polyacrylonitrile (PAN)- or mesophase pitch (MPP)-based carbon fibres. Their Young's modulus values are therefore drastically lower (\(100\ \rm{GPa}\); tensile strength \(100\ \rm{MPa}\)). Rayon-based carbon fibres can be transformed into anisotropic carbon fibres with high strength and Young's modulus values by hot-stretching treatment at temperatures of approximately \(2800\ \rm{K}\).