The Detonation Synthesis, Characters Of Nano Graphite And It's Application In The Al Matrix Composite Materials

Detonation is a better way in preparing nanographite (nmGr) extensively. Gr-Al matrix composite materials are used in wear-resistant parts and damping of vibration parts because of their excellent characters. The detonation synthesis, characters and application in the Al matrix composite materials were researched chiefly in this paper. The main contents are follows:1) The preparation methods and application fields of nmGr were summarized;2) The influences of different explosion density, kinds and pressure of protection atmosphere on the yield of nmGr were researched. The yield of nmGr increases with the raise of density of explosion;the yield of nmGr is higher when the protection atmosphere is CO2 comparing to Ar, N2, He and low vacuum;When the pressure of the protection atmosphere adds to 2 atm, the yield of nmGr is higher;3) The structure of nmGr obtained from detonation is hexagonal. The pattern of nano graphite is sphere or sphere-like;X-ray diffraction microscopy, laser Raman analysis, specific surface analysis and transmission electron microscope analysis all indicate that the size of nano graphite's is nanometer;The surface of the nano graphite contains C-H, -NO2, -HCOH, quinonyl etal atom groups;4) The research state of Gr-Al matrix composite materials was summarized;their preparation method was explored. The results indicate that through hot pressing can obtain better nmGr-Al matrix composite materials sinter. Hot pressing can increase the density of composite materials;when the weight percent of the nmGr is 1, the dispersion of the nano graphite is homogeneous;5) When the weight percent of nano graphite is not more than 2, the tensile strength of the composite materials is unable to decrease, but micron graphite (equal weight percent) can make the tensile strength of the composite materials decrease;6) The friction coefficient and loss of wear can decrease when the nmGr is added in the Al-6.3Mg composite materials. The friction coefficient can decrease obviously when the nano graphite is added in the Al-0.8Mg-l.4Si composite materials, bur the loss of wear increases with the increases of nmGr percentage;When the weight percent of the Gr added in the 6061A1 is 1, the loss of wear rate is lower when nmGr as additive, but when the weight percent of the Gr added in the 6061 Al is 2, the loss of wear is lower when μmGr as additive;7) The damping of Al-0.8Mg-Si alloys increases when the nmGr is added in them. For 6061 alloys, the nmGr and μmGr can all make the damping factors increase, but the damping factors of nmGr added in the composites are higher than μmGr added in the composites.