In-Situ Synthesis Of Graphene-Copper Composites Based On Carbonization Of Small Molecular Carbon Sources

Modern electronic information,power energy and other fields have put forward higher and higher performance requirements for copper-based materials,and the development of copper-based composite materials with excellent comprehensive performance has become the focus of copper material research.The two-dimensional nanomaterial graphene is considered to be an ideal reinforcement for copper-based composites due to its excellent comprehensive properties.However,in the research of graphene/copper composites,there are still poor graphene dispersion uniformity and reinforcement and matrix.The problem of poor interface integration.These two problems are the key bottlenecks that restrict graphene/copper composite materials to industrial applications.Aiming at the above problems,this paper uses the in-situ growth method to prepare graphene-coated copper structure composite powders based on the carbonization method of small molecular carbon sources,and then prepares graphene/copper composite materials through a vacuum hot pressing sintering process.This paper first studied the effect of carbon source types on the carbonization effect.Using nine small molecule carbon sources such as sucrose,the surface of commercial copper powder was uniformly coated by rotary evaporation method,and the copper-carbon catalytic mechanism was used to composite the surface at high temperature.The powder was carbonized to prepare graphene/copper composite powder.After analyzing the tissue structure and chemical structure,it is found that sucrose,glucose,and lactose are the high-quality precursor carbon sources for the in-situ growth method.On this basis,the sucrose carbon source was selected,and the effects of carbonization temperature and carbonization time on the quality of graphene after carbonization were further studied.After the analysis results,it was found that the sp~2 carbon content of sucrose was relatively high after carbonization at 675?and 750?,and the graphene crystallized The degree of crystallization is relatively high.When the carbonization time is 10 min,the content of sp~2 carbon is relatively high,and the degree of crystallization of graphene is relatively high.The graphene/copper composite material was prepared by a densification sintering process.Research on the structure of graphene in the composite material showed that the high-temperature sintering process further improved the crystallization degree of graphene.The performance test of the composite material found that the addition of graphene effectively improved the hardness and tensile strength of the composite material.At the same time,the room temperature electrical conductivity and thermal conductivity of the composite material were still maintained at a high level,which was mainly due to the graphene's Good crystallinity makes it possible to realize its excellent intrinsic properties.After testing,the engineering thermal expansion coefficient of the composite material is slightly lower than that of pure copper.This is because the graphene existing at the grain boundary limits the expansion of the copper grains.Because the graphene volume fraction is low,the engineering thermal expansion coefficient decreases.Smaller.The graphene/copper composite material was deformed by hot rolling at 500°C,and an annealing process was used in the rolling.After rolling,the graphene exhibits a highly oriented arrangement along the rolling direction.The performance of the rolled composite material was tested,and it was found that the hardness,tensile strength,elongation at break and electrical conductivity of the composite material were significantly improved after rolling.The improvement of the mechanical and electrical transport properties of the rolled composite material is mainly due to the hot rolling process that causes the micropores and other defects in the composite material to be welded,and the hot rolling reduces the structural defects in the composite material.In summary,this article uses small molecule carbon source carbonization method,in-situ growth method,vacuum hot pressing sintering process to obtain graphene/copper composite material,and realizes the hot rolling deformation of the composite material,and obtains excellent comprehensive performance The graphene/copper composite material and its performance have been studied.Through this research,it is expected that a graphene/copper composite preparation method with excellent comprehensive performance,simple process,economic and environmental protection and mass production can be realized,and it will contribute to the early breakthrough of the industrial application bottleneck of graphene/copper composites.