Carbon Nanotube Reinforced Aluminum Matrix Composite

Abstract

The invention discloses a carbon-nanotube-reinforced aluminum-base composite material which is prepared by the following steps: 1) carrying out high-speed shear mixing on predispersed carbon nanotubes and an adhesive until the adhesive is uniformly coated on the carbon nanotube surface, adding pure aluminum powder or aluminum alloy powder, and carrying out high-speed shear mixing until the carbon nanotubes are uniformly distributed on the pure aluminum powder or aluminum alloy powder surface, thereby obtaining first composite powder; 2) carrying out ball milling on the obtained first composite powder to obtain second composite powder; and 3) sequentially carrying out sinter molding and hot extrusion molding to obtain the carbon-nanotube-reinforced aluminum-base composite material. The adverse factors capable of resulting in stratification due to density variation are eliminated, so that the CNTs (carbon nanotubes) and the aluminum powder are uniformly mixed while keeping favorable sintering activity, and the bonding strength between the CNTs and aluminum powder is enhanced to obtain favorable interfacial combination. The combined action of work hardening and grain refining reinforcement on the base can be utilized to enhance the aluminum base, so that the tensile strength and wear resistance of the composite material are greatly enhanced.

Description

Technical field [0001] The invention relates to an aluminum-based composite material, in particular to a carbon nanotube reinforced aluminum-based composite material. Background technique [0002] Carbon nanotubes have excellent properties such as mechanics, optics, electricity, high temperature resistance, corrosion resistance, and light weight, which makes them an ideal enhancer. Theoretical and experimental studies on the mechanical properties of carbon nanotubes have shown that carbon nanotubes have good toughness, stable structure, extremely small scale and excellent mechanical properties, and are ideal one-dimensional nano-reinforced and toughened materials. [0003] There have been some reports on the effect of carbon nanotubes as a reinforcing material on improving the strength, hardness, friction, wear performance and thermal stability of metals. Aluminum and aluminum alloys have the characteristics of light weight, good rigidity, and low thermal expansion coefficient. Al...

AI Technical Summary

Problems solved by technology

For example, in the invention patents with publication numbers CN1546695A, CN1730688A, and CN101613079A, the preparation technology of carbon nanotube-reinforced aluminum-based composite materials is introduced, but there are many deficiencies in these three technologies. Specifically, for the first technology Said that the preparation of composite materials by its pressureless impregnation process is carried out at high temperature, and the impregnation time is long, which leads to the generation of a large number of interface reactants, which is not conducive to the improvement of mechanical properties; for the second technology, its vapor deposition The preparation of composite materials by in-situ reaction needs to grow carbon nanotubes on the surface of the powder. Although the uniform distribution of CNTs can be achieved, the process is cumbersome and the cost is high, which is not conducive to industrial production; and for the third technology, carbon nanowhiskers Due to the pickling treatment, the surface morphology of CNTs is seriously damaged, and the pickling treatment takes a long time, which is not conducive to industrial production

Moreover, the simple ball milling mixing process is adopted in the aforementioned three invention patents, and the uniform mixing of CNTs and aluminum powder cannot be achieved well, and the two cannot be effectively combined

[0005] In fact, there are various methods for preparing carbon nanotube-reinforced metal matrix composites, including powder metallurgy process, melting solidification process, thermal spraying process, electrochemical deposition process, etc., the most commonly used method is basically powder metallurgy process, and The process of mechanical alloying in the powder metallurgy process is difficult to control. At the same time, due to the large aspect ratio of CNTs, it is easy to agglomerate. It is difficult to achieve good dispersion of CNTs by completely using the ball milling process, and in CNTs There is a large density difference between CNTs and Al powder, which can easily lead to delamination of CNTs and Al powder and cannot be well combined, thereby affecting the performance of the prepared carbon nanotube aluminum matrix composite.

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