阅读说明：本技术 氮化硼纳米片增强的铝基复合材料制备方法 (Preparation method of boron nitride nanosheet reinforced aluminum-based composite material ) 是由 何春年 马立世 于 2019-09-19 设计创作，主要内容包括：本发明涉及一种氮化硼纳米片增强的铝基复合材料制备方法,包括如下步骤：原料为铝粉与氮化硼纳米片,按铝粉与氮化硼纳米片质量比(96-99):(1-4)的比例,将铝粉与氮化硼纳米片装入球磨罐中,在惰性气体氛围下,通过球磨使铝粉与氮化硼纳米片混合均匀；将球磨后的粉末装入磨具,冷压成型；将冷压块体进行半固态烧结,烧结温度为600-750℃,烧结时间为1-3小时；将半固态烧结后的块体置于挤压装置进行挤压,得到原位生成的均匀连续浸润层的铝基复合材料。(The invention relates to a preparation method of a boron nitride nanosheet reinforced aluminum-based composite material, which comprises the following steps: the method comprises the following steps of (1) putting aluminum powder and boron nitride nanosheets into a ball milling tank according to the mass ratio (96-99) to (1-4) of the aluminum powder to the boron nitride nanosheets, and uniformly mixing the aluminum powder and the boron nitride nanosheets through ball milling in an inert gas atmosphere; putting the ball-milled powder into a grinding tool, and performing cold press molding; semi-solid sintering is carried out on the cold-pressed block body, the sintering temperature is 600-750 ℃, and the sintering time is 1-3 hours; and (3) placing the semi-solid sintered block body in an extrusion device for extrusion to obtain the aluminum-based composite material of the uniform and continuous infiltration layer generated in situ.)

1. A preparation method of a boron nitride nanosheet reinforced aluminum-based composite material is characterized by comprising the following steps:

(1) The raw materials are aluminum powder and boron nitride nanosheets, the aluminum powder and the boron nitride nanosheets are filled into a ball milling tank according to the mass ratio of (96-99) to (1-4), and the aluminum powder and the boron nitride nanosheets are uniformly mixed through ball milling in an inert gas atmosphere.

(2) Putting the ball-milled powder into a grinding tool, and performing cold press molding;

(3) Semi-solid sintering is carried out on the cold-pressed block body, the sintering temperature is 600-750 ℃, and the sintering time is 1-3 hours;

(4) And (3) placing the semi-solid sintered block body in an extrusion device for extrusion to obtain the aluminum-based composite material of the uniform and continuous infiltration layer generated in situ.

Technical Field

The invention belongs to the technical field of composite materials, and particularly relates to a method for preparing a boron nitride nanosheet reinforced aluminum-based composite material by adopting a semi-solid sintering method.

Background

The aluminum-based composite material has the advantages of high strength, small density, corrosion resistance, good thermal stability and the like, and is increasingly widely applied to the fields of automobiles, electronics, sports industry, aerospace, aviation and the like. The novel two-dimensional material reinforced aluminum-based composite material has good comprehensive performance, high reinforcing efficiency, large development potential, easy realization of large-scale production, wide application prospect in the industrial field and great application potential. The boron nitride nanosheet (h-BN) has excellent performances of strength close to that of graphene, high oxidation resistance temperature, low expansion coefficient, good thermal conductivity and the like, and is an ideal composite material reinforcing phase. With the commercial production of artificially synthesized boron nitride nanosheets, the preparation technology is greatly improved, so that the cost of artificially synthesized boron nitride nanosheets is gradually reduced, and the application range of the artificially synthesized boron nitride nanosheets is gradually expanded to various aspects of composite material preparation.

In the case of composite materials, improving the interface bonding between the reinforcing phase and the matrix is a key factor for improving the comprehensive performance of the composite material. The traditional preparation method of the two-dimensional material reinforced aluminum-based composite material comprises hot-pressing sintering and plasma sintering, the prepared composite material has weak interface combination, cannot form a continuous interface wetting layer, mostly forms second-phase particles on the interface, causes low strength and toughness, and limits the application range of the composite material.

Therefore, the interface bonding strength of the composite material prepared by the currently adopted preparation method of the two-dimensional material reinforced aluminum-based composite material needs to be improved, and at present, no literature report is found on a technology which can simply and quickly prepare the boron nitride nanosheet reinforced aluminum-based composite material and can generate a continuous wetting layer.

disclosure of Invention

Aiming at the problems, the invention provides a semi-solid sintering preparation method of a boron nitride nanosheet reinforced aluminum-based composite material, which can be used for preparing the boron nitride nanosheet reinforced aluminum-based composite material with a continuous wetting layer. The technical scheme is as follows:

A preparation method of a boron nitride nanosheet reinforced aluminum-based composite material is characterized by comprising the following steps:

(1) The method comprises the following steps of (1) putting aluminum powder and boron nitride nanosheets into a ball milling tank according to the mass ratio (96-99) to (1-4) of the aluminum powder to the boron nitride nanosheets, and uniformly mixing the aluminum powder and the boron nitride nanosheets through ball milling in an inert gas atmosphere;

(2) Putting the ball-milled powder into a grinding tool, and performing cold press molding;

(3) semi-solid sintering is carried out on the cold-pressed block body, the sintering temperature is 600-750 ℃, and the sintering time is 1-3 hours;

(4) and (3) placing the semi-solid sintered block body in an extrusion device for extrusion to obtain the aluminum-based composite material of the uniform and continuous infiltration layer generated in situ.

The invention has the following advantages:

The preparation method of the BN nanosheet reinforced aluminum-based composite material has the characteristics of short time, simple process, low production cost and suitability for industrial production. The block aluminum-based composite material prepared by the method has a continuous interface wetting layer, is clean and has higher strength.

Compared with the prior art, the boron nitride nanosheet reinforced aluminum-based composite material prepared by the invention adopts a semi-solid state sintering condition, and the mass fraction of the boron nitride nanosheet is changed between 1-8%; the fracture strength of the composite material is 200-400MPa, and the fracture elongation is 5-20%; this series of parameters is significantly higher than conventional means (hot pressing or plasma) sintering.

Drawings

FIG. 1 is a scanning electron microscope image of a boron nitride nanosheet mixed with aluminum powder;

fig. 2 is a transmission electron microscope image of the boron nitride nanosheet reinforced aluminum-based composite obtained by the method in the embodiment of the invention.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.