热压烧结Gr/6061Al复合材料制备与组织性能研究

Reach of the preparation, Microstructure and Properties of Gr / 6061Al Composites sintered by Hot Pressing Sintering

摘要:

实验采用了热压烧结的方法制备了1~25vol%片层石墨(Gr)含量的Gr/6061Al复合材料,并采用了纳米铝粉包覆片层石墨的混粉工艺提高片层石墨在铝基体粉末中的分散均匀性。所制备的复合材料中,片层石墨均匀分散在铝基体中,界面结合良好,未发现界面反应产物的存在,通过透射电镜观察到了少层石墨烯的存在。1~15vol% Gr含量的Gr/6061Al复合材料的致密度均高于90%；复合材料的致密度和摩擦系数随着片层石墨含量的增加具有相同的变化趋势,都逐渐降低；石墨含量从1vol%增加到25vol%时,复合材料摩擦系数(COF)呈逐渐降低的趋势；与1vol.%Gr含量的Gr/6061Al复合材料相比,其他Gr含量的复合材料的磨损率均较高。

Abstract:

The graphite sheet (Gr)/6061Al composites with Gr content of 1~25vol.% were prepared by vacuum hot-pressure sintering. The nano-aluminum powders were adopted as cladding materials on the surface of graphite sheet to improve the dispersal uniformity of graphite sheet within aluminum matrix. The graphite sheet dispersed uniformly in the aluminum matrix, and the interface between aluminum and Gr was well integrated without interfacial reaction product being found. The presence of few layer graphene was observed by transmission electron microscopy (TEM). The relative densities of the Gr/6061Al composites with 1~15vol% Gr content are all higher than 90%. The relative densities of the samples were decreased with the increasing of graphite content; and the coefficient of friction(COF) of the samples possess the same trend. The wear rate of the samples with Gr content of 5vol.%, 10vol.%, 15vol.% and 25vol.% are all higher than that with 1vol.% Gr content.An experimental set-up was designed for measuring the self-field losses of Bi2223/Ag HTS tapes using a transport current method.