CN109338134A - A kind of preparation method of nickel-plated carbon nanotube reinforced aluminum matrix composite material - Google Patents

Abstract

The invention relates to a preparation method of a nickel-plated carbon nanotube reinforced aluminum-based composite material. The steps are as follows: (1) surface roughening of carbon tubes: adding carbon nanotubes into a NaOH solution to roughen the surface; (2) carbon nanotubes Nanotube surface sensitization: the surface roughened carbon nanotubes are added to a mixed solution of SnCl ₂ and HCl for treatment. After the treatment, the carbon nanotubes are washed with deionized water. (3) Surface activation of carbon nanotubes: the carbon nanotubes after surface sensitization treatment are added to the mixed solution of PbCl2 and HCl for surface activation; ( ₄ ) Ni plating on the surface of carbon nanotubes: the surface is roughened, The sensitized and activated carbon nanotubes were electroless Ni-plated in Ni nitrate solution; (5) the forming of nickel-plated carbon nanotube-reinforced composites.

Description

A kind of preparation method of nickel-plated carbon nanotube reinforced aluminum matrix composite material

technical field

The invention relates to a preparation method for improving the mechanical properties of an aluminum matrix composite material by using a cold pressing-sintering molding method, and belongs to the field of powder metallurgy.

Background technique

In recent years, with the development of modern industries such as aviation, aerospace, automobile manufacturing and military industry, metal matrix composites have ushered in a wide range of application prospects due to their excellent properties. Among them, aluminum-based composite materials are the focus of development and research, because aluminum-based composite materials have many properties that other materials do not have, such as good corrosion resistance, low density, workability and high temperature resistance, etc. . However, with the rapid development of modern industry, higher requirements have also been placed on the performance of aluminum matrix composites in all aspects. Therefore, the traditional reinforcing phases such as whiskers, ceramic particles and fibers used in the preparation of aluminum matrix composites can no longer meet the current needs. Therefore, how to improve the comprehensive properties of aluminum matrix composites has become a research hotspot in recent years.

Carbon nanotubes have been favored by scientific researchers since their discovery in 1991. This is due to the low density, high chemical stability and very high mechanical properties of carbon nanotubes. Therefore, carbon nanotubes are considered as an ideal reinforcement phase for the preparation of aluminum matrix composites. At present, the main methods for preparing aluminum matrix composites include powder metallurgy, melt casting, pressure infiltration and friction stir welding. Among them, powder metallurgy is widely used in the preparation of carbon nanotube reinforced aluminum matrix composites due to its advantages of simple operation and low sintering temperature. However, there are still two challenges in the preparation of carbon nanotube-reinforced aluminum matrix composites by powder metallurgy: one is the agglomeration of carbon nanotubes in the aluminum matrix due to the van der Waals force between carbon nanotubes; The problem of non-wetting of nanotubes with aluminum matrix. Therefore, it is of great significance to solve the dispersibility of carbon nanotubes in the aluminum matrix, improve the interface wettability between carbon nanotubes and aluminum, and establish a stable carbon-aluminum interface.

SUMMARY OF THE INVENTION

The purpose of the present invention is to propose a preparation method of a novel nickel-plated carbon nanotube reinforced aluminum matrix composite material, mainly by loading nickel nanoparticles on the surface of the carbon nanotube to improve the non-wetting phenomenon between the carbon nanotube and the aluminum matrix, Finally, the mechanical properties of aluminum matrix composites are significantly improved. In order to achieve the above objects, the present invention is achieved through the following technical solutions.

A preparation method of nickel-plated carbon nanotube reinforced aluminum-based composite material, the steps are as follows:

(1) surface roughening of carbon tubes: adding carbon nanotubes to NaOH solution to roughen the surface;

(2) Carbon nanotube surface sensitization: the surface roughened carbon nanotubes are added to a mixed solution of SnCl ₂ and HCl for treatment, and after the treatment is completed, the carbon nanotubes are washed with deionized water.

(3) Surface activation of carbon nanotubes: The carbon nanotubes after surface sensitization treatment are added to the mixed solution of PbCl ₂ and HCl for surface activation;

(4) Ni plating on the surface of carbon nanotubes: the carbon nanotubes whose surface has been roughened, sensitized and activated are electrolessly plated with Ni in a nitrate solution of Ni;

(5) Forming of nickel-plated carbon nanotube-reinforced composite material: the nickel-plated carbon nanotube powder and aluminum powder obtained in steps (1)-(4) are placed in a stainless steel ball mill in a mass ratio of 1:100-300. In the tank, the ratio of ball to material is 1:10, and argon gas is used as protective gas, and the mixed powder is ball-milled; the mixed composite powder is first cold-pressed at 500-600Mpa, and then in an argon atmosphere, the temperature is The sintering is carried out for 1 hour under the condition of 600-630 DEG C, and then the obtained bulk material is hot-extruded under the condition of 500-600 DEG C, and then a nickel-plated carbon nanotube-reinforced composite material is obtained.

In (2), the mixed solution of SnCl ₂ and HCl, the concentration of SnCl ₂ is 8-12g/L, and the concentration of HCl is 35-45ml/L.

In (3), the mixed solution of PbCl ₂ and HCl, the concentration of PbCl ₂ is 0.8-1.2g/L, and the concentration of HCl is 25-35ml/L.

In the present invention, nickel-plated carbon nanotubes are firstly plated on the surface of carbon nanotubes by a chemical method, so that the surface of carbon nanotubes can be loaded with even nano-nickel particles; The quality of the tube can effectively solve the problem of the dispersion of carbon nanotubes; finally, the bulk composite material is prepared by the method of cold pressing and sintering-hot extrusion. The introduction of nickel can not only solve the problem of non-wetting between carbon nanotubes and aluminum, but also avoid excessive interfacial reaction between carbon nanotubes and aluminum matrix, and achieve a significant improvement in the mechanical properties of aluminum matrix composites. .

Description of drawings

FIG. 1 is an SEM image of the nickel-plated carbon nanotubes prepared in Examples 1 and 2. FIG. The figure shows that there are many nickel particles with a size of tens of nanometers distributed on the surface of the carbon tube.

FIG. 2( a ) is a TEM image of the nickel-plated carbon nanotubes prepared in Examples 1 and 2. FIG. The supported nickel particles can be more clearly observed from this figure.

FIG. 2( b ) is a TEM image of the nickel-plated carbon nanotubes prepared in Examples 1 and 2. FIG. From this figure, it can be seen that the carbon nanotubes still maintain a good structure except for supporting nickel particles.

Figures 2(c), (d) and (e) are the energy spectrum analysis results of the nickel-coated carbon nanotubes prepared in Examples 1 and 2 under transmission. It can be seen from this figure that nickel elements are uniformly distributed on the carbon nanotubes, and there is no agglomeration phenomenon, and at the same time, there are some oxygen elements on the carbon nanotubes.

3 is the stress-strain curve of the composite materials prepared in Examples 1 and 2 of the present invention and the pure aluminum prepared in Comparative Example 1.

Detailed ways

The present invention is described below in conjunction with specific examples, but does not limit the present invention.

Example 1

(1) 1 g of carbon nanotubes was added to a NaOH solution with a concentration of 200 g/L, and the surface was roughened for 20 min at 80°C;

(2) The surface-roughened carbon nanotubes were added to a mixed solution of SnCl ₂ (10 g/L) and HCl (40 ml/L), and treated at 30° C. for 3 min. After the treatment, the carbon nanotubes were treated with Wash with deionized water;

(3) The carbon nanotube replacement tube after surface sensitization treatment is added to the mixed solution of PbCl ₂ (1g/L) and HCl (30ml/L) for surface activation;

(4) The carbon nanotubes whose surface has been roughened, sensitized and activated are electrolessly plated with Ni in a Ni nitrate solution, and the electrolyte is composed of NiSO ₄ ·6H ₂ O (20g/L), CuSO ₄ ·5H Composition of ₂ O (1.2g/L), C ₆ H ₈ O ₇ (15g/L), H ₃ BO ₃ (40g/L) and NaH ₂ PO ₂ (40g/L) Electroless Ni plating was performed on the surface of the nanotubes for 1h.

(5) The nickel-plated carbon nanotube powder obtained in steps (1)-(4) was placed in a 250ml stainless steel ball mill in a mass fraction of 1% and 15g of aluminum powder with a particle size of 20-30μm, wherein the ratio of ball to material was 1:10 with argon as protective gas. The mixed powder was subjected to variable-speed ball milling at 200 rpm for 6 h and 400 rpm for 2 h, in order to fully mix the reinforcing phase and the aluminum powder on the premise of ensuring the quality of the carbon nanotubes. The mixed composite powder was cold-pressed for 3 minutes at a pressure of 600Mpa, and then sintered in an argon atmosphere with a temperature of 630°C for 1h, and then the obtained bulk material was subjected to hot extrusion at 550°C, and then the obtained Nickel-coated carbon nanotube-reinforced rod-like composites.

(6) Tensile specimens were prepared with the prepared rod-shaped composite material, and tensile properties were tested.

The tensile strength of the Ni-CNTs reinforced aluminum matrix composite prepared in this example is 214.9MPa and 27.7% in the cold-pressed sintered-hot extrusion state. The results are shown in the curve of Example 1 in Figure 3.

Example 2

(1) 1 g of carbon nanotubes was added to a NaOH solution with a concentration of 200 g/L, and the surface was roughened for 20 min at 80°C;

(2) The surface-roughened carbon nanotubes were added to a mixed solution of SnCl ₂ (10 g/L) and HCl (40 ml/L), and treated at 30° C. for 3 min. After the treatment, the carbon nanotubes were treated with Wash with deionized water;

(3) The carbon nanotube replacement tube after surface sensitization treatment is added to the mixed solution of PbCl ₂ (1g/L) and HCl (30ml/L) for surface activation;

(4) The carbon nanotubes whose surface has been roughened, sensitized and activated are electrolessly plated with Ni in a Ni nitrate solution, and the electrolyte is composed of NiSO ₄ ·6H ₂ O (20g/L), CuSO ₄ · Composition of 5H ₂ O (1.2g/L), C ₆ H ₈ O ₇ (15g/L), H ₃ BO ₃ (40g/L) and NaH ₂ PO ₂ (40g/L) at 70℃ Electroless Ni plating on the surface of carbon nanotubes for 1h.

(5) The nickel-plated carbon nanotube powder obtained in steps (1)-(4) was placed in a 250ml stainless steel ball mill in a mass fraction of 2% and 15g of aluminum powder with a particle size of 20-30μm, wherein the ratio of ball to material was 1:10 with argon as protective gas. The mixed powder was subjected to variable-speed ball milling at 200 rpm for 6 h and 400 rpm for 2 h, in order to fully mix the reinforcing phase and the aluminum powder on the premise of ensuring the quality of the carbon nanotubes. The mixed composite powder was cold-pressed at a pressure of 600Mpa for 3 minutes, and then sintered for 1 hour in an argon atmosphere at a temperature of 630°C, and the obtained bulk material was hot-extruded at a temperature of 550°C. After pressing, a rod-shaped composite reinforced with nickel-coated carbon nanotubes was obtained.

(6) Tensile specimens were prepared with the prepared rod-shaped composite material, and tensile properties were tested.

The tensile strength of the Ni-CNTs reinforced aluminum matrix composite prepared in this example in the state of cold pressing and sintering-hot extrusion is 275.3MPa, and the elongation is 20.1%. The results are shown in the curve of Example 2 in Figure 3.

Comparative Example 1

(1) 15g of aluminum powder with a particle size of 20-30μm was placed in a 250ml stainless steel ball mill jar, wherein the ball-to-material ratio was 1:10, and argon was used as the protective gas. The mixed powder was subjected to variable-speed ball milling at 200 rpm for 6 h and 400 rpm for 2 h, respectively. The ball-milled powder was cold-pressed for 3 minutes at a pressure of 600Mpa, and then sintered in an argon atmosphere at a temperature of 630°C for 1h, and then the obtained bulk material was subjected to hot extrusion at a temperature of 550°C. , and then a rod-shaped material of pure aluminum is obtained.

(6) Tensile specimens are prepared with the obtained rod-shaped material, and tensile properties are tested.

The tensile strength of the pure aluminum prepared in this example in the cold-pressed sintered-hot extrusion state is 126.9 MPa, and the elongation is 22.3%. The results are shown in the curve of Comparative Example 1 in FIG. 3 .

Claims (3)

1. a kind of preparation method of nickel-plating carbon nanotube reinforced aluminum matrix composites, steps are as follows:

(1) carbon pipe surface is roughened: carbon nanotube being added in NaOH solution, roughing in surface is carried out；

(2) carbon nano tube surface is sensitized: the carbon nanotube after roughing in surface is added to SnCl₂It is carried out in the mixed solution of HCl Processing washes carbon nanotube with deionized water after completion processing.

(3) carbon nano tube surface activates: treated that carbon nanometer changes pipe is added to PbCl for surface sensitizing₂In the mixed solution of HCl Carry out surface active；

(4) Ni is plated on carbon nanotube surface: by surface into the carbon nanotube crossed after being roughened, be sensitized and activating in the nitrate solution of Ni Carry out Electroless Plating Ni；

(5) nickel-plating carbon nanotube enhancing composite material molding: by nickel-plating carbon nanotube powder made from step (1)-(4) with The ratio of aluminium powder 1:100~300 in mass ratio is placed in stainless steel jar mill, wherein ratio of grinding media to material be 1:10, and using argon gas as Mixed-powder is carried out ball milling by protective gas；Mixed composite powder is first carried out to the cold moudling of 500-600Mpa, later In an argon atmosphere, temperature carries out the sintering of 1h under conditions of being 600-630 DEG C, then by obtained block materials 500~600 Hot extrusion is carried out under the conditions of DEG C, obtains the composite material of nickel-plating carbon nanotube enhancing later.

2. preparation method according to claim 1, which is characterized in that (2) in, SnCl₂With the mixed solution of HCl, SnCl₂ Concentration be 8-12g/L, the concentration of HCl is 35-45ml/L.

3. preparation method according to claim 1, which is characterized in that (3) in, PbCl₂With the mixed solution of HCl, PbCl₂ Concentration be 0.8-1.2g/L, the concentration of HCl is 25-35ml/L.