CN115725913B - Reinforced aluminum-based composite material and preparation method thereof - Google Patents

Abstract

The invention discloses a reinforcement-reinforced aluminum matrix composite material and a preparation method thereof. The composite material includes a reinforcement layer and an aluminum substrate layer. The reinforcement layer and the aluminum substrate layer are randomly overlapped. The ratio of the total volume of the reinforcement layer to the total volume of the aluminum substrate layer is 1:4.5-9. This composite material is based on the synergy between each layer. By controlling the volume ratio of the reinforcement layer and the aluminum substrate layer, it not only effectively reduces the amount of reinforcement added, but also greatly improves the fracture toughness of the material. This composite mold hot pressing process does not need to be carried out in a vacuum environment or protective atmosphere. By controlling the mold temperature to be slightly lower than the solid solution point of the aluminum substrate, the infiltration depth and bonding force between the aluminum substrate and the reinforcement can be controlled, greatly improving the composite quality. Material tensile strength.

Description

Reinforcement-reinforced aluminum matrix composite material and preparation method thereof

Technical field

The invention relates to an aluminum-based composite material, in particular to a reinforcement-reinforced aluminum-based composite material and a preparation method thereof, and belongs to the field of composite materials.

Background technique

Aluminum-based composite materials have been widely used in aerospace, automobiles, electronic packaging and other fields due to their excellent properties such as low density, high specific strength, high specific modulus, high wear resistance and low thermal expansion coefficient. However, with the development of science and technology, especially the increasing requirements for material performance in the aerospace field, there is an urgent need to improve the performance of aluminum-based composite materials. At present, aluminum matrix composite materials are mainly divided into particle reinforced aluminum matrix composite materials and fiber reinforced aluminum matrix composite materials. Although particle reinforced aluminum matrix composite materials have high strength, they have poor fracture toughness and insufficient reliability. Fiber reinforced aluminum matrix composite materials, especially continuous fiber reinforced aluminum matrix composite materials, can not only ensure the strength of the composite material, but also It can improve the fracture toughness and impact resistance of materials.

In the existing technology, in order to achieve a good combination between the reinforcement and the matrix, the requirements for the manufacturing environment are relatively high. The furnace body is required to be in a vacuum or under the protection of an argon or nitrogen atmosphere, and because the wettability of silicon carbide and the aluminum matrix is poor The problem is that the suppression time is longer.

Contents of the invention

In view of the problems existing in the prior art, the first purpose of the present invention is to provide a reinforcement-reinforced aluminum-based composite material. The composite material is based on the synergy between each layer and controls the volume ratio of the reinforcement layer and the aluminum substrate layer. , not only effectively reduces the amount of reinforcement added, but also greatly improves the tensile strength and fracture toughness of the material.

The second object of the present invention is to provide a method for preparing reinforcement-reinforced aluminum-based composite materials. This method adopts a mold hot pressing process without using a vacuum process. By controlling the mold temperature to be slightly lower than the solid solution point of the aluminum substrate, the method Controlling the wettability and bonding force between the aluminum substrate and the reinforcement, combined with the chemical plating modification and overlapping layering of the surface of the reinforcement, further improves the bonding strength between the aluminum substrate and the reinforcement, thereby achieving the tensile strength and Significant improvement in fracture toughness.

In order to achieve the above technical objectives, the present invention provides a reinforcement-reinforced aluminum-based composite material, including a reinforcement layer and an aluminum substrate layer; the reinforcement layer and the aluminum substrate layer are randomly overlapped, and any two reinforcement layers At least one layer of aluminum substrate is included between them; the ratio of the total volume of the reinforcement layer to the total volume of the aluminum substrate layer is 1:4.5-9.

The composite material provided by the present invention is based on the synergistic effect between the reinforcement layer and the aluminum substrate layer and is composed of a random overlapping method, which increases the contact area of the reinforcement layer to the aluminum substrate layer and improves the fracture toughness of the composite material; Strictly control the volume ratio between the reinforcement layer and the aluminum substrate layer, thereby controlling the bonding force between the reinforcement and the aluminum substrate, which not only effectively reduces the amount of reinforcement added, but also greatly increases the tensile strength of the composite material.

The volume ratio of the reinforcement layer to the aluminum substrate layer must be strictly in accordance with the above ratio. If too much reinforcement layer is added, the fibers will not be completely surrounded by the aluminum matrix. As a result, there will be no aluminum matrix between some fibers and there will be no aluminum matrix between them. The load cannot be effectively transmitted during the process, which affects the overall strength; if the amount of reinforcement layer added is too small, the performance of the reinforcement phase cannot be exerted, which directly affects the reinforcement effect.

As a preferred solution, the surface of the reinforcement layer is covered with a metal plating layer, and the thickness of the metal plating layer is 0.2-2 μm. The thickness of the metal coating must strictly comply with the above requirements. If the thickness of the metal coating is too low, the polarity between the reinforcement and the aluminum substrate will be too large and the wetting effect cannot be achieved. If the thickness of the metal coating is too high, the metal coating will be easy to Falling off and cracking from the surface of the reinforcement layer will instead reduce the bonding force between the reinforcement and the aluminum substrate layer.

As a preferred solution, the reinforcement layer is silicon carbide fiber cloth, and the silicon carbide content in the silicon carbide fiber cloth is 85 to 95%. The purity of the silicon carbide fiber cloth used in the present invention must be strictly implemented in accordance with the above requirements. If the purity of the silicon carbide fiber cloth is too low, the strengthening effect on the aluminum substrate cannot be achieved, and it cannot meet the high temperature and high pressure preparation process in a non-vacuum environment.

As a preferred solution, the metal plating layer is a copper layer and/or a nickel layer.

As a preferred solution, the thickness of the aluminum substrate layer is 0.1 to 0.8 mm.

As a preferred solution, the aluminum substrate layer is at least one of series 2 aluminum alloy, series 6 aluminum alloy and series 7 aluminum alloy.

The invention also provides a method for preparing a reinforcement-reinforced aluminum-based composite material. The reinforcement layer is degummed and then subjected to electroless plating to obtain a plated reinforcement layer; the plated reinforcement layer is combined with an aluminum substrate from which the oxide film has been removed. The layers are laid in the mold, and are obtained after molding and holding pressure in sequence.

The preparation method provided by the invention adopts a mold hot pressing process, which does not need to be carried out in a vacuum environment or a protective atmosphere. By controlling the mold temperature to be slightly lower than the solid solution point of the aluminum substrate, the infiltration depth and bonding between the aluminum substrate and the reinforcement can be controlled. force, greatly improving the tensile strength and fracture toughness of composite materials.

As a preferred solution, the glue removal process is to heat the reinforcement layer and then clean it with a solvent; the conditions for the glue removal process are: temperature 570-630°C, time 30-60 minutes.

As a preferred solution, the solvent is any one of water, ethanol and acetone.

As a preferred solution, the solvent cleaning conditions are: ultrasonic cleaning for 10 to 20 minutes.

As a preferred solution, the method for removing the oxide layer from the aluminum substrate is any one of strong acid cleaning, strong alkali cleaning and grinding removal.

As a preferred solution, the molding conditions are: pressure is 50-120MPa, and temperature is 630-650°C. The molding process must be carried out strictly in accordance with the above requirements. Among them, the temperature must be slightly lower than the solid solution point of the aluminum substrate to ensure that the aluminum substrate is in a semi-fluid state. If the temperature is too high, the aluminum substrate will be too soft or in a molten state, making rapid forging impossible. ; If the temperature is too low, the aluminum substrate will be too hard and will not be able to form an effective bond with the reinforcement. On the contrary, cracks will occur due to rapid stamping, reducing the mechanical properties of the composite material.

As a preferred solution, the pressure maintaining conditions are: the pressure is 50-120MPa and the time is 5-30s.

Compared with the prior art, the advantages of the present invention are:

1) The composite material provided by the present invention is based on the synergy between each layer. By controlling the volume ratio of the reinforcement layer and the aluminum substrate layer, it not only effectively reduces the amount of reinforcement added, but also greatly improves the tensile strength and fracture of the material. toughness.

2) In the technical solution provided by the present invention, the mold hot pressing process is adopted, which does not need to be carried out in a vacuum environment or protective atmosphere. By controlling the mold temperature to be slightly lower than the solid solution point of the aluminum substrate, the relationship between the aluminum substrate and the reinforcement is controlled. The wettability and bonding force, combined with the electroless plating modification and overlapping layering on the surface of the reinforcement, further enhance the bonding strength between the aluminum substrate and the reinforcement, thereby achieving a substantial increase in the tensile strength and fracture toughness of the composite material.

3) In the technical solution provided by the present invention, through rapid stamping integrated molding, rapid molding is achieved while ensuring the mechanical strength of the composite material, greatly shortening the preparation time, effectively reducing the preparation cost, increasing product productivity, and facilitating Large-scale industrial production.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are: For some embodiments of the present invention, those of ordinary skill in the art can also obtain other drawings based on these drawings without exerting creative efforts;

Figure 1 is an SEM of the copper-plated fiber preform monofilament prepared in Example 1;

Figure 2 is a SEM of the fracture surface of the composite plate prepared in Example 1;

Figure 3 is a scanning electron microscope of the composite plate prepared in Example 1.

Detailed ways

In order to facilitate understanding of the present invention, the present invention will be described more comprehensively and in detail below with reference to the accompanying drawings and preferred embodiments. However, the protection scope of the present invention is not limited to the following specific embodiments.

Unless otherwise defined, all technical terms used below have the same meanings as commonly understood by those skilled in the art. The technical terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of the present invention.

Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased in the market or prepared by existing methods.

Example 1

A method for preparing silicon carbide fiber cloth-reinforced aluminum-based composite panels, including the following steps:

(1) Treatment of silicon carbide fiber cloth: Remove the glue from the silicon carbide fiber cloth at 600°C for 30 minutes. After the glue is removed, clean it with acetone for 10 minutes, then dry it and then electroless copper plating to obtain a silicon carbide fiber cloth containing a copper layer. Prefab;

(2) Treatment of aluminum substrates: Use aluminum alloy rolled plates with model number 6061 and a thickness of 0.3mm. Polish and polish to remove the oxide film 30 minutes before entering the furnace for heating;

(3) Preparation of the final sample: Place the silicon carbide fiber cloth preform and the aluminum substrate alternately in the mold in the order of aluminum substrate - silicon carbide fiber cloth prefab - aluminum substrate, heat it to 630°C, apply a pressure of 100MPa, and keep After pressing for 5 seconds, the silicon carbide fiber cloth reinforced aluminum matrix composite plate is obtained;

The size of the silicon carbide fiber cloth reinforced aluminum matrix composite material prepared in this example is The volume fraction of silicon carbide fiber reinforcement is about 18%, and the tensile strength can reach 350Mpa.

Example 2

A method for preparing silicon carbide fiber cloth-reinforced aluminum-based composite panels, including the following steps:

(1) Treatment of silicon carbide fiber cloth: Remove the glue from the silicon carbide fiber cloth at 600°C for 30 minutes. After the glue is removed, clean it with acetone for 10 minutes, then dry it and then electroless copper plating to obtain a silicon carbide fiber cloth containing a copper layer. Prefab;

(2) Treatment of aluminum substrates: Use aluminum alloy rolled plates with model number 6061 and a thickness of 0.3mm. Clean them with 30% NaOH solution and 20% HNO3 solution to remove the oxide film 30 minutes before entering the furnace for heating;

(3) Preparation of the final sample: Place the silicon carbide fiber cloth preform and the aluminum substrate alternately in the mold in the order of aluminum substrate - silicon carbide fiber cloth prefab - aluminum substrate, heat it to 650°C, apply a pressure of 50MPa, and keep After pressing for 15 seconds, the silicon carbide fiber cloth reinforced aluminum matrix composite plate is obtained;

The size of the silicon carbide fiber bundle reinforced aluminum matrix composite material prepared in the example is The volume fraction of silicon carbide fiber reinforcement is about 15%, and the tensile strength reaches 330Mpa.

Comparative example 1

A method for preparing silicon carbide fiber cloth-reinforced aluminum-based composite panels, including the following steps:

(1) Treatment of silicon carbide fiber cloth: remove the glue from the silicon carbide fiber cloth at 600°C for 30 minutes, and then clean it with acetone for 10 minutes after the glue is removed to obtain the silicon carbide fiber cloth preform;

(2) Treatment of aluminum substrates: Use aluminum alloy rolled plates with model number 6061 and a thickness of 0.3mm. Polish and polish to remove the oxide film 30 minutes before entering the furnace for heating;

(3) Preparation of the final sample: Alternately lay the silicon carbide fiber cloth preform and the aluminum substrate prefabricated body in the mold in the order of aluminum substrate - silicon carbide fiber cloth prefab - aluminum substrate and heat it to 650°C, then apply a pressure of 20MPa , after maintaining pressure for 1 hour, the silicon carbide fiber cloth reinforced aluminum matrix composite plate is obtained;

The size of the silicon carbide fiber bundle reinforced aluminum matrix composite material prepared in the example is The volume fraction of silicon carbide fiber reinforcement is about 40%, and the tensile strength is 100Mpa.

Comparative example 2

A method for preparing silicon carbide fiber cloth-reinforced aluminum-based composite panels, including the following steps:

(1) Treatment of silicon carbide fiber cloth: Remove the glue from the silicon carbide fiber cloth at 600°C for 30 minutes. After the glue is removed, clean it with acetone for 10 minutes, then dry it and then electroless copper plating to obtain a silicon carbide fiber cloth containing a copper layer. Prefab;

(2) Treatment of aluminum substrates: Use aluminum alloy rolled plates with model number 6061 and a thickness of 0.3mm. Clean them with 30% NaOH solution and 20% HNO ₃ solution to remove the oxide film 30 minutes before entering the furnace for heating;

(3) Preparation of the final sample: Place the silicon carbide fiber cloth preform and the aluminum substrate alternately in the mold in the order of aluminum substrate - silicon carbide fiber cloth prefab - aluminum substrate, and place the mold in a vacuum hot pressing furnace , pump the vacuum degree to less than 10 ^-2 Pa, raise the temperature to 650°C, apply a pressure of 50MPa, and maintain the pressure for 15 seconds to obtain the silicon carbide fiber cloth reinforced aluminum matrix composite plate;

The size of the silicon carbide fiber bundle reinforced aluminum matrix composite material prepared in the example is The volume fraction of silicon carbide fiber reinforcement is about 15%, and the tensile strength reaches 320Mpa.

Comparative example 3

A method for preparing silicon carbide fiber cloth-reinforced aluminum-based composite panels, including the following steps:

(1) Treatment of silicon carbide fiber cloth: Remove the glue from the silicon carbide fiber cloth at 600°C for 30 minutes. After the glue is removed, clean it with acetone for 10 minutes, then dry it and then electroless copper plating to obtain a silicon carbide fiber cloth containing a copper layer. Prefab;

(2) Treatment of aluminum substrates: Use aluminum alloy rolled plates with model number 6061 and a thickness of 0.3mm. Polish and polish to remove the oxide film 30 minutes before entering the furnace for heating;

(3) Preparation of the final sample: Place the silicon carbide fiber cloth preform and the aluminum substrate alternately in the mold in the order of aluminum substrate - silicon carbide fiber cloth prefab - aluminum substrate, heat it to 600°C, apply a pressure of 100MPa, and keep After pressing for 5 seconds, the silicon carbide fiber cloth reinforced aluminum matrix composite plate is obtained;

The size of the silicon carbide fiber cloth reinforced aluminum matrix composite material prepared in this example is The volume fraction of silicon carbide fiber reinforcement is about 18%, and the tensile strength can reach 118Mpa.

Claims (7)

1. A reinforcement-reinforced aluminum-based composite material, characterized in that: it includes a reinforcement layer and an aluminum substrate layer; the reinforcement layer and the aluminum substrate layer are randomly overlapped, and any two reinforcement layers include at least An aluminum substrate layer; the total volume ratio of the reinforcement layer to the aluminum substrate layer is 1:4.5~9; The preparation process of the aluminum-based composite material is as follows: remove the glue from the reinforcement layer and perform electroless plating treatment to obtain a plated reinforcement layer; lay the plated reinforcement layer and the aluminum substrate layer with the oxide film removed in a mold, After molding and holding pressure in sequence, it is obtained; The molding conditions are: pressure is 50~120MPa, temperature is 630~650°C; The conditions for maintaining the pressure are: the pressure is 50~120MPa and the time is 5~30s. 2. A reinforcement reinforced aluminum matrix composite material according to claim 1, characterized in that: the surface of the reinforcement layer is covered with a metal plating layer, and the thickness of the metal plating layer is 0.2~2 μm. 3. A reinforcement reinforced aluminum matrix composite material according to claim 2, characterized in that: the reinforcement layer is silicon carbide fiber cloth, and the silicon carbide content in the silicon carbide fiber cloth is 85~95%; The metal plating layer is a copper layer and/or a nickel layer. 4. A reinforcement reinforced aluminum matrix composite material according to claim 1, characterized in that: the thickness of the aluminum substrate layer is 0.1~0.8mm; the aluminum substrate layer is 2 series aluminum alloy, 6 series aluminum At least one of alloys and 7 series aluminum alloys. 5. A kind of reinforcement-reinforced aluminum-based composite material according to claim 1, characterized in that: the glue removal process is to use solvent cleaning after heating the reinforcement layer; the conditions of the glue removal process are: temperature 570 ~ 630℃, time is 30~60min. 6. A reinforcement reinforced aluminum matrix composite material according to claim 5, characterized in that: the solvent is any one of water, ethanol and acetone; the solvent cleaning conditions are: ultrasonic cleaning for 10~ 20min. 7. A reinforcement reinforced aluminum matrix composite material according to claim 1, characterized in that: the method for removing the oxide film from the aluminum substrate layer is any one of strong acid washing, strong alkali washing and grinding removal. kind.