In order to expand the damping temperature range and improve the damping performance of fluorinerubber(FKM),a series of NMK/FKM nanocomposites were prepared by filling different proportion of nano-metakaolin(NMK) into the FKM matrix by melt blending method.The thermodynamic analysis,basic mechanical properties test and scanning electron microscope analysis of NMK/FKM nanocomposites with different mass fraction of NMK were carried out to study their damping properties,static mechanical properties and microstructure.The results show that nano-metakaolin filler can significantly improve the damping property and tensile strength of fluororubber.With the increase of filling content of nano-metakaolin,the damping property of NMK/FKM nanocomposites is improved continuously.When the mass fraction of NMK is 20%,the wide damping temperature range is increased to 79.41 ℃ and the tensile strength reaches 12.8 MPa,which is 217.64% and 43.82% higher than that of pure FKM respectively.The reason is that NMK is one kind of nanoscale material,which has unique advantages in providing weak cation exchange and strong ion adsorption,and may play a certain role in enhancing the interaction between NMK and FKM molecules.