CN108359852A - A kind of high silica/aluminum-based composite material and preparation method of graphene enhancing - Google Patents

Abstract

A kind of high silica/aluminum-based composite material and preparation method of graphene enhancing, composite material contain ingredient by mass percentage：Silicon：15.0~20.0%, copper：2.0~4.0%, magnesium：0.5~1.0%, titanium：0.05~0.07%, boron：0.02~0.05%, graphene：0.3~0.6%, surplus is aluminium；Preparation method：1) by each ingredient of raw material, under gas shield, batch mixing obtains alloy powder；2) after alloy powder being pressed into blocky sintered blank material, vacuum-sintering obtains sintered blank；3) it is directed to the content of different silicon, quenching treatment+temper or multiway forging+annealing are carried out to it, the high silica/aluminum-based composite material of graphene enhancing is made；The method of the present invention makes reinforced phase distribution of particles evenly, and generates a large amount of dislocations in material internal, and dislocation born of the same parents are broken into subgrain or fine grain, reach refined crystalline strengthening；Its tensile strength is increased to 400MPa or more；The yield strength of material is increased to 236MPa or more simultaneously.

Description

A kind of graphene-reinforced high-silicon-aluminum matrix composite material and preparation method thereof

technical field

The invention relates to the field of graphene application technology, in particular to a graphene-reinforced high-silicon-aluminum matrix composite material and a preparation method thereof.

Background technique

Aluminum-silicon composite materials have the advantages of high specific strength and specific stiffness, low thermal expansion coefficient, good wear resistance and volume stability, and high enough high temperature strength, and are widely used in aerospace and automobile manufacturing industries. When the silicon content exceeds 12.6% of the Al-Si eutectic point, although the strength is further improved, due to the increased size and irregular shape of the silicon particles embedded in the matrix, the matrix is severely split, and stress is formed at the tip of the silicon phase. Concentration reduces the tensile strength of the material and deteriorates the machinability of the material. At present, the silicon content of commonly used aluminum-silicon-based composite materials is basically lower than that of eutectic components. The reinforcements of aluminum-silicon-based composite materials are mainly divided into particle reinforcement and fiber reinforcement, but their production costs are high, and particle reinforcement and fiber reinforcement are used. The potential for further reinforcement of aluminum matrix composites is diminishing.

Contents of the invention

Aiming at the deficiencies of the prior art, the invention provides a graphene-reinforced high-silicon-aluminum matrix composite material and a preparation method thereof.

The graphene-enhanced high-silicon aluminum-based composite material of the present invention contains the following components by mass percentage: silicon: 15.0-20.0%, copper: 2.0-4.0%, magnesium: 0.5-1.0%, titanium: 0.05-0.07%, boron : 0.02 to 0.05%, graphene: 0.3 to 0.6%, and the balance is aluminum.

The above-mentioned graphene-enhanced high-silicon-aluminum-based composite material contains the first preferred solution in terms of mass percentage: silicon: 15.0-18.0%, copper: 3.0-4.0%, magnesium: 0.5-1.0%, titanium: 0.05- 0.06%, boron: 0.02-0.03%, graphene: 0.3-0.6%, and the balance is aluminum.

The above-mentioned graphene-enhanced high-silicon aluminum-based composite material contains the second preferred solution in terms of mass percentage: silicon: 18.0-20.0%, copper: 2.0-3.0%, magnesium: 0.5-1.0%, titanium: 0.06-0.07% , boron: 0.03-0.05%, graphene: 0.3-0.6%, and the balance is aluminum.

The preparation method of the high-silicon-aluminum-based composite material reinforced by graphene of the present invention specifically comprises the following steps:

Step 1, mixing ingredients:

After batching according to the composition percentage of the graphene-reinforced high-silicon-aluminum matrix composite material, under the protection of inert gas or nitrogen, put it into a mixing tank, mix at a speed of 30-50r/min for 24-36 hours, and let it stand for 1-2 hours Finally, mix the materials at a speed of 30-40r/min for 24-36 hours, let it cool down to room temperature, and obtain a uniformly mixed alloy powder;

Step 2, molding and sintering:

(1) Pour the uniformly mixed alloy powder into a pressing mold under the protection of an inert gas, hold the pressure at 220-250MPa for 5-8min, and demould to obtain a block-shaped sintered billet;

(2) Carry out vacuum sintering on the bulk sintered billet, the sintering temperature is 560-575°C, and the sintering time is 1.5-2 hours, then cool to room temperature with the furnace to obtain the sintered billet;

Step 3, subsequent heat treatment:

For the composition ratio of the graphene-enhanced high-silicon-aluminum matrix composite material in step 1, when 15.0%≤silicon mass percentage content<18%, the following treatments (a) and (b) are adopted:

(a) Quenching treatment is carried out on the sintered blank, the quenching temperature is 500°C, water cooling after holding time for 1 to 3 hours;

(b) Tempering the quenched billet, the tempering temperature is 150-200°C, the holding time is 1-3h, and then air-cooled to obtain a graphene-enhanced high-silicon-aluminum matrix composite material;

For the composition ratio of the graphene-enhanced high-silicon-aluminum-based composite material in step 1, when the mass percentage of 18.0%≤silicon≤20.0%%, the following treatments (c) and (d) are adopted:

(c) Multi-directional forging is carried out on the sintered blank, the forging temperature is 480-500°C, the deformation speed is 2-4mm/s, and the forging deformation direction is changed for each forging pass;

(d) performing annealing treatment on the forged billet at an annealing temperature of 180-200° C. and an annealing time of 1-3 hours to obtain a graphene-reinforced high-silicon-aluminum matrix composite material.

The preparation method of the above-mentioned graphene-reinforced high-silicon-aluminum-based composite material, wherein:

In said step 1, loading into the mixing tank is carried out in a gas protection glove isolation box.

In the step 1, the inert gas is argon.

In the step 1, the mixing is carried out in a three-dimensional space motion mixing ball mill.

In the step 1, the mixture is mixed at a speed of 30-40r/min for 24-36 hours and then left to stand for 1-2 hours. The purpose is to prevent the temperature of the mixing tank from rising due to continuous rotation for a long time, causing cold welding of the powder in the tank. Therefore, stop for 1 ~ 2h.

In the step 2, a 0.5MN double-column manual hydraulic press is used for molding.

In the step 2, a vacuum hot-press sintering furnace is used for vacuum sintering.

In the step 2, the sintering time is determined depending on the amount of alloy powder.

In the step 3, a resistance furnace is used for the quenching treatment. The quenching and holding time is determined according to the size of the part.

In the step 3, a double-column manual hydraulic press is used for multi-directional forging.

In the step 3, a total of 5 to 10 passes of forging are carried out.

Graphene itself is a new type of high-performance nanomaterial with high strength, good flexibility, excellent electrical and thermal conductivity and optical properties. Because of its unique structure, it has Dirac-Fermi characteristics, singular quantum Hall effect and minimum quantum conductivity. and other properties. Compared with traditional reinforcements, it has larger specific strength, specific surface area and lower production cost, making it the most ideal reinforcement material to replace ceramic fibers, carbon nanotubes and hard particles. At present, high-silicon aluminum alloys such as A390, ZL117, and KS282, which are common at home and abroad, have a silicon content of about 15% to 22%, which has higher specific strength and lower thermal expansion coefficient, and is especially suitable for aircraft model and motorcycle piston materials. As the silicon content increases, coarse polygonal block or plate silicon particles appear, and the mechanical properties, especially the elongation, decrease significantly. Improving the morphology and distribution of silicon particles in the aluminum matrix and making the silicon particles fine and dispersed is crucial to improving the mechanical properties of high-silicon-aluminum-based materials. The addition of graphene significantly improves the morphology of silicon particles in the high-silicon-aluminum matrix composite material, has a refinement effect on silicon particles, and improves the comprehensive mechanical properties of the aluminum-silicon composite material.

Compared with the prior art, the graphene-reinforced high-silicon aluminum-based composite material and the preparation method thereof of the present invention have the beneficial effects of:

The invention prepares a high-performance graphene-reinforced high-silicon-aluminum matrix composite material with high strength and hardness by selecting a specific formula, and also has light weight, wear resistance, high thermal conductivity, low thermal expansion coefficient, and good cutting process Performance advantages, and also has excellent thermal conductivity, can be widely used in aerospace, precision instruments and automobile manufacturing fields.

The addition of graphene nanomaterials improves the tensile strength and yield strength of the high-silicon-aluminum matrix composites, and its elongation also increases. The addition of graphene nanosheets makes the silicon particles in the high-silicon-aluminum matrix composite structure fine and dispersed, and the tensile strength of the material increases from 328MPa to over 400MPa, an increase of more than 20%; at the same time, the yield strength of the material increases from 202MPa The above increases to above 236MPa. Its improved effect is obviously better than that of other materials reinforced high-silicon-aluminum matrix composites. The addition of graphene improved the morphology and distribution of silicon particles, resulting in improved yield strength and plasticity.

With the increase of Si content, the thermal cracking resistance of the composite material is improved. In order to maximize the strength of the graphene-aluminum-silicon-based multi-component composite material, for graphene-reinforced high-silicon-aluminum-based composite materials with a Si content close to 20%, multiple The forging process can make the distribution of reinforcement phase particles more uniform, and generate a large number of dislocations inside the material, and the dislocation cells are broken into sub-grains or fine grains to achieve the effect of fine-grain strengthening.

Description of drawings

The microstructure morphology of the high-silicon-aluminum matrix composite material prepared by Fig. 1 embodiment 1 of the present invention reinforced by graphene;

The microstructure morphology of the high-silicon-aluminum-based composite material reinforced by graphene reinforced by Fig. 2 of the present invention embodiment 2;

The microstructure morphology of the high-silicon-aluminum matrix composite material prepared by Fig. 3 embodiment 3 of the present invention reinforced by graphene;

Fig. 4 is the microstructure morphology of the graphene-reinforced high-silicon-aluminum matrix composite material prepared in Example 4 of the present invention.

Detailed ways

Example 1

A graphene-reinforced high-silicon-aluminum matrix composite material, containing components by mass percentage: silicon: 15.0%, copper: 4.0%, magnesium: 1.0%, titanium: 0.06%, boron: 0.03%, graphene: 0.5% , with aluminum as the balance.

The preparation method of the above-mentioned graphene-enhanced high-silicon-aluminum-based composite material specifically comprises the following steps:

Step 1, mixing ingredients:

The composition of the graphene-reinforced high-silicon-aluminum matrix composite is 15.0% silicon, 4.0% copper, 1.0% magnesium, 0.06% titanium, 0.03% boron, 0.5% graphene, and aluminum as the balance.

In the glove isolation box under the protection of argon, the 700-mesh various raw material powders are batched according to the above mass percentages and put into the mixing tank, and then the mixing tank is assembled on the ball mill, and then in the three-dimensional space motion mixing ball mill , mixed at a speed of 40r/min for 30 hours, and after standing for 1 hour, the purpose is to prevent the temperature of the mixing tank from rising due to continuous rotation for a long time, causing cold welding of the powder in the tank, repeat the continuous rotation and mixing for 30 hours, and let it stand After dissipating heat to normal temperature, it is unloaded from the ball mill to obtain evenly mixed alloy powder;

Step 2, molding and sintering:

(1) Pour the uniformly mixed alloy powder into a pressing mold under the protection of argon, adopt a 0.5MN double-column manual hydraulic press, hold the pressure at 240MPa for 5min, and demould to obtain a block-shaped sintered blank;

(2) Carry out vacuum sintering to block-shaped sintered blanks in a vacuum hot-pressing sintering furnace at a sintering temperature of 560° C. and after sintering for 2 hours, cool to room temperature with the furnace to obtain a sintered blank;

Step 3, subsequent heat treatment:

(1) For the sintered billet, use a resistance furnace for quenching treatment, the quenching temperature is 500 ° C, the holding time is 2 hours (can be determined according to the size of the sintered part), and then water cooling;

(2) Tempering the quenched billet, the tempering temperature is 180°C, air cooling after 2 hours of holding time, and a graphene-enhanced high-silicon-aluminum matrix composite material is obtained; its microstructure is shown in Figure 1, in the figure The dark particles are Si particles, and the off-white area is mostly Al ₂ Cu phase.

Example 2

A graphene-reinforced high-silicon-aluminum matrix composite material, containing components by mass percentage: silicon: 16.0%, copper: 3.5%, magnesium: 1.0%, titanium: 0.06%, boron: 0.03%, graphene: 0.3% , with aluminum as the balance.

The preparation method of the above-mentioned graphene-enhanced high-silicon-aluminum-based composite material specifically comprises the following steps:

Step 1, mixing ingredients:

The composition of the graphene-reinforced high-silicon-aluminum matrix composite is 16.0% silicon, 3.5% copper, 1.0% magnesium, 0.06% titanium, 0.03% boron, 0.3% graphene, and aluminum as the balance.

In the glove isolation box under the protection of argon, the 700-mesh various raw material powders are batched according to the above mass percentages and put into the mixing tank, and then the mixing tank is assembled on the ball mill, and then in the three-dimensional space motion mixing ball mill , mixed at a speed of 40r/min for 30 hours, and after standing for 1 hour, the purpose is to prevent the temperature of the mixing tank from rising due to continuous rotation for a long time, causing cold welding of the powder in the tank, repeat the continuous rotation and mixing for 30 hours, and let it stand After dissipating heat to normal temperature, it is unloaded from the ball mill to obtain evenly mixed alloy powder;

Step 2, molding and sintering:

(1) Pour the uniformly mixed alloy powder into a pressing mold under the protection of argon, adopt a 0.5MN double-column manual hydraulic press, hold the pressure at 240MPa for 5min, and demould to obtain a block-shaped sintered blank;

(2) Carry out vacuum sintering to block-shaped sintered billets in a vacuum hot-pressing sintering furnace, the sintering temperature is 575°C, and the sintering time is 1.52 hours, and then cooled to room temperature with the furnace to obtain a sintered billet;

Step 3, subsequent heat treatment:

(1) For the sintered billet, use a resistance furnace for quenching treatment, the quenching temperature is 500 ° C, the holding time is 2 hours (can be determined according to the size of the sintered part), and then water cooling;

(2) Tempering the quenched blank, the tempering temperature is 180°C, air cooling after 2 hours of holding time, and a graphene-reinforced high-silicon-aluminum matrix composite material is obtained; its microstructure is shown in Figure 2.

Example 3

A graphene-reinforced high-silicon-aluminum matrix composite material, containing components by mass percentage: silicon: 20.0%, copper: 2.0%, magnesium: 1.0%, titanium: 0.07%, boron: 0.04%, graphene: 0.6% , with aluminum as the balance.

The preparation method of the above-mentioned graphene-enhanced high-silicon-aluminum-based composite material specifically comprises the following steps:

Step 1, mixing ingredients:

The composition of the graphene-reinforced high-silicon-aluminum matrix composite is 20.0% silicon, 2.0% copper, 1.0% magnesium, 0.07% titanium, 0.04% boron, 0.6% graphene, and aluminum as the balance.

In the glove isolation box under the protection of argon, the 700-mesh various raw material powders are batched according to the above mass percentages and put into the mixing tank, and then the mixing tank is assembled on the ball mill, and then in the three-dimensional space motion mixing ball mill , mixed at a speed of 40r/min for 30 hours, and after standing for 1 hour, the purpose is to prevent the temperature of the mixing tank from rising due to continuous rotation for a long time, causing cold welding of the powder in the tank, repeat the continuous rotation and mixing for 30 hours, and let it stand After dissipating heat to normal temperature, it is unloaded from the ball mill to obtain evenly mixed alloy powder;

Step 2, molding and sintering:

(1) Pour the uniformly mixed alloy powder into a pressing mold under the protection of argon, adopt a 0.5MN double-column manual hydraulic press, hold the pressure at 240MPa for 5min, and demould to obtain a block-shaped sintered blank;

(2) Carry out vacuum sintering to block-shaped sintered billets in a vacuum hot-pressing sintering furnace, the sintering temperature is 565°C, and the sintering time is 1.8 hours, and then cooled to room temperature with the furnace to obtain a sintered billet;

Step 3, subsequent heat treatment:

(1) Using a double-column manual hydraulic press, multi-directional forging is carried out on the sintered billet, and a total of 5 forging passes are carried out. The forging temperature is 490°C, and the deformation speed is 3mm/s. The forging deformation direction is changed for each forging pass;

(2) Annealing the forged billet with an annealing temperature of 200° C. and an annealing time of 2 hours to prepare a graphene-reinforced high-silicon-aluminum matrix composite material. Its microstructure is shown in Figure 3.

Example 4

A graphene-reinforced high-silicon-aluminum matrix composite material, containing components by mass percentage: silicon: 19.0%, copper: 2.5%, magnesium: 1.0%, titanium: 0.06%, boron: 0.04%, graphene: 0.5% , with aluminum as the balance.

The preparation method of the above-mentioned graphene-enhanced high-silicon-aluminum-based composite material specifically comprises the following steps:

Step 1, mixing ingredients:

The composition of the graphene-reinforced high-silicon-aluminum matrix composite is 19.0% silicon, 2.5% copper, 1.0% magnesium, 0.06% titanium, 0.04% boron, 0.5% graphene, and aluminum as the balance.

In the glove isolation box under the protection of argon, the 700-mesh various raw material powders are batched according to the above mass percentages and put into the mixing tank, and then the mixing tank is assembled on the ball mill, and then in the three-dimensional space motion mixing ball mill , mixed at a speed of 40r/min for 30 hours, and after standing for 1 hour, the purpose is to prevent the temperature of the mixing tank from rising due to continuous rotation for a long time, causing cold welding of the powder in the tank, repeat the continuous rotation and mixing for 30 hours, and let it stand After dissipating heat to normal temperature, it is unloaded from the ball mill to obtain evenly mixed alloy powder;

Step 2, molding and sintering:

(1) Pour the uniformly mixed alloy powder into a pressing mold under the protection of argon, adopt a 0.5MN double-column manual hydraulic press, hold the pressure at 240MPa for 5min, and demould to obtain a block-shaped sintered billet;

(2) Carry out vacuum sintering of block-shaped sintered blanks in a vacuum hot-pressing sintering furnace, the sintering temperature is 570°C, and the sintering time is 1.5 to 2 hours, and then cooled to room temperature with the furnace to obtain a sintered blank;

Step 3, subsequent heat treatment:

(1) Using a double-column manual hydraulic press, multi-directional forging is carried out on the sintered billet, and a total of 10 forging passes are carried out. The forging temperature is 490°C and the deformation speed is 3mm/s. The forging deformation direction is changed for each forging pass;

(2) Annealing the forged billet with an annealing temperature of 200° C. and an annealing time of 2 hours to prepare a graphene-reinforced high-silicon-aluminum matrix composite material. Its microstructure is shown in Figure 4.

Claims (7)

1. a kind of high silica/aluminum-based composite material of graphene enhancing, which is characterized in that be by mass percentage containing ingredient：Silicon： 15.0~20.0%, copper：2.0~4.0%, magnesium：0.5~1.0%, titanium：0.05~0.07%, boron：0.02~0.05%, graphite Alkene：0.3~0.6%, surplus is aluminium.

2. the high silica/aluminum-based composite material of graphene enhancing according to claim 1, which is characterized in that press matter containing ingredient Measuring percentage is：Silicon：15.0~18.0%, copper：3.0~4.0%, magnesium：：0.5~1.0%, titanium：0.05~0.06%, boron： 0.02~0.03%, graphene：0.3~0.6%, surplus is aluminium.

3. the high silica/aluminum-based composite material of graphene enhancing according to claim 1, which is characterized in that press matter containing ingredient Measuring percentage is：Silicon：18.0~20.0%, copper：2.0~3.0%, magnesium：0.5~1.0%, titanium：0.06~0.07%, boron： 0.03~0.05%, graphene：0.3~0.6%, surplus is aluminium.

4. the preparation method of the high silica/aluminum-based composite material of graphene enhancing described in claim 1, which is characterized in that specific packet Include following steps：

Step 1, batch mixing：

After percentage composition dispensing by the high silica/aluminum-based composite material of graphene enhancing, under inert gas or nitrogen protection, It is packed into mixing tank, with rotating speed 24~36h of batch mixing of 30~50r/min, after standing 1~2h, then it is mixed with the rotating speed of 30~40r/min Expect 24~36h, stands heat dissipation to room temperature, obtain uniformly mixed alloy powder；

Step 2, molding sintering：

(1) alloy powder that will be uniformly mixed, pours into compacting tool set under inert gas protection, 220~250MPa pressurizes 5~ 8min, demoulding obtain blocky sintering blank；

(2) vacuum-sintering, 560~575 DEG C of sintering temperature, after 1.5~2h of sintering time, with furnace cooling are carried out to bulk sintering blank But to room temperature, sintered blank is obtained；

Step 3, subsequent heat treatment：

For the composition proportion for the high silica/aluminum-based composite material that graphene in step 1 enhances, when the quality percentage of 15.0%≤silicon When content ＜ 18%, using following processing (a) and (b)：

(a) to sintered blank, quenching treatment is carried out, hardening heat is 500 DEG C, water cooling after 1~3h of soaking time；

(b) by quenched blank, temper is carried out, temperature is 150~200 DEG C, air-cooled after 1~3h of soaking time, The high silica/aluminum-based composite material of graphene enhancing is made；

For the composition proportion for the high silica/aluminum-based composite material that graphene in step 1 enhances, when the quality percentage of 18.0%≤silicon When content≤20.0%%, using following processing (c) and (d)：

(c) multiway forging is carried out to sintered blank, forging temperature is 480~500 DEG C, and deformation velocity is 2~4mm/s, often Passage forging changes forging deformation direction；

(d) it by the blank after forging, is made annealing treatment, 180~200 DEG C, 1~3h of annealing time of annealing temperature, graphite is made The high silica/aluminum-based composite material of alkene enhancing.

5. the preparation method of the high silica/aluminum-based composite material of graphene enhancing described in claim 1, which is characterized in that the step In rapid 1, being fitted into mixing tank is carried out in gas shield gloves shielded box；Batch mixing in three-dimensional space motion batch mixing ball mill into Row；In the step 2, molding uses 0.5MN double-column hand-operated hydraulic press, vacuum-sintering to use vacuum sintering funace；The step In rapid 3, quenching treatment uses resistance furnace, multiway forging to use double-column hand-operated hydraulic press.

6. the preparation method of the high silica/aluminum-based composite material of graphene enhancing described in claim 1, which is characterized in that the step In rapid 1, inert gas is argon gas.

7. the preparation method of the high silica/aluminum-based composite material of graphene enhancing described in claim 1, which is characterized in that the step In rapid 3, the forging of 5~10 passages is carried out altogether.