Preparation And Properties Of Cnts Enhance The Aluminum-based Nanocomposites

In this paper,carbon nanotubes(CNTs)/ aluminum composite material was prepared by powder metallurgy ways.Microstructure and mechanical properties of composite was also preliminary study.In order to increase the CNTs and Al matrix wettability,carbon nanotubes were dispersed by the ultrasonic treatment.By mechanical ball milling method, CNTs was pretreatment and then the CNTs/Al composite powder was produce,The composite powder morphology was studied by using scanning electron microscopy (SEM);Chunk CNTs/Al composites was prepared by use of vacuum hot-press sintering and Its mechanical and physical properties are discussed.The results show that after ultrasonic dispersion of carbon nanotubes,the nanotubes tend to reduce the reunion and increase dispersion.By mechanical ball milling method to control aspect ratio of carbon nanotubes are more suitable for 3-5 in a matrix of aluminum reinforcement.By vacuum hot-press sintering process we can get a good performance of CNTs /Al composite material.SEM results show that carbon nanotubes uniformly distributed in the Al matrix.Content of CNTs 2.0wt%,hot pressing pressure 20 MPa,hot pressing time 20 min,hot pressing temperature 600℃,Relative density of Composite materials is 99.13%,hardness can achieve maximum 50.2HV.The content of carbon nanotubes and the properties of the composite are closely related.it shown that the tensile strength of composite is 83MPa,Its tensile strength compared to pure aluminum(59MPa)increased 41%.Its yield strength (116MPa)than the matrix increased by 24%.With the CNTs content increases further,due to the role of increased reunion,composite materials tensile strength and yield strength decline.The CNTs / Al composites fracture surface was analysis and found that carbon nanotubes were a good combination of Al matrix composite materials,Its fracture mode was ductile fracture.Effects of CNTs content on the friction and wear properties of composite were studied.The best content of carbon nanotubes of composite is 2%,CNTs/Al composite material significantly reduced the wear debris and worn surface becomes relatively smooth,friction and wear properties is stable.