CN101942587A - Magnesium alloy pumice ferric oxide cobalt composite material and preparation method thereof - Google Patents

Abstract

The invention provides a magnesium alloy pumice iron oxide cobalt composite material and a preparation method thereof. The composite material has high wave-absorbing performance and excellent damping performance. The method has simple process, low production cost and is suitable for industrialized production. The composite material uses a magnesium alloy as a matrix, and pumice iron oxide cobalt complexes and dolomite particles are distributed on the matrix, and the pumice iron oxide cobalt complexes and dolomite particles account for 40-45% of the volume of the composite material; the composite The particle size is 0.5-1mm; the weight percentage of the chemical composition of the magnesium alloy matrix: Al is 4%-8%, Th is 0.01%-0.05%, Si is 0.5%-1%, Bi is 0.001%- 0.005%, the rest is Mg.

Description

Magnesium alloy pumice iron oxide cobalt composite material and preparation method thereof

1. Technical field

The invention belongs to the field of metal materials, and relates to a magnesium alloy pumice iron oxide cobalt wave-absorbing and vibration-damping composite material and a preparation method thereof.

2. Background technology

At present, in the field of materials, the wave-absorbing and vibration-reducing effect of materials has been paid attention to.

CN200410023374.1 relates to an aluminum-based wave-absorbing material and its preparation method, which is characterized in that: the surface layer of an aluminum or aluminum alloy plate is formed by a one-step or two-step anodic oxidation method of direct current or alternating current to form a porous aluminum oxide film to form an aluminum-based porous oxide film Aluminum template, that is, AAO template; use DC or pulse current electrochemical deposition to assemble magnetic nano-metal wire arrays in aluminum-based AAO porous membranes to make aluminum-based absorbing materials for in-situ assembly of magnetic nanowire arrays on the surface. The disadvantage of this method is that it requires high technical difficulty.

CN200910071958.9 proposes a ceramic whisker/ferromagnetic metal composite wave-absorbing material and a preparation method thereof, which relates to a composite material for absorbing electromagnetic waves and a preparation method thereof. Ceramic whiskers coated with ferromagnetic metal coatings are heat-treated for 60 minutes at a temperature of 300-400°C and the heat treatment atmosphere is hydrogen or argon to obtain ceramic whisker/ferromagnetic metal composite wave-absorbing materials. The disadvantage of this method is that the surface of the ceramic whisker is coated with a ferromagnetic metal coating, and the ferromagnetic metal is easy to fall off during processing.

Application No. CN200910191481.8 relates to a preparation method of a short carbon fiber reinforced magnesium-based composite material with excellent damping properties, which includes the following steps: (1) removing the organic glue layer on the surface of the short carbon fiber; (2) depositing metal nickel coating by electroless plating layer, under alkaline conditions by controlling the deposition time to obtain the required thickness of the coating; (3) After the short carbon fiber coated with metal nickel coating is prepared, the powder metallurgy method can be used to prepare the carbon fiber with excellent damping characteristics Short carbon fiber reinforced magnesium matrix composites. The invention adds 3 to 20% by volume of electroless nickel-plated short carbon fibers into the magnesium matrix. Although the matrix is strengthened and the damping performance is endowed with better performance, its damping performance is better than that of pure magnesium, which can reach High damping range of 0.015, but the process is more complicated. The disadvantage of this material is its poor absorbing properties.

3. Contents of the invention

The object of the present invention is to address the above-mentioned technical defects and provide a magnesium alloy pumice iron oxide cobalt composite material, which has high wave-absorbing performance and excellent damping performance.

Another object of the present invention is to provide a preparation method of magnesium alloy pumice iron oxide cobalt wave-absorbing and vibration-damping composite material. The preparation method has simple process, low production cost and is suitable for industrial production.

The purpose of the present invention is achieved through the following technical solutions:

A magnesium alloy-based pumice iron oxide cobalt composite material, the composite material takes magnesium alloy as a matrix, and pumice iron oxide cobalt complexes and dolomite particles are distributed on the matrix, and the pumice iron oxide cobalt complexes and dolomite particles account for The volume percentage of the composite material is 40-45%; the size of the composite particles is 0.5-1mm; the weight percentage of the chemical composition of the magnesium alloy matrix: Al is 4%-8%, Th is 0.01%-0.05%, Si is 0.5%-1%, Bi is 0.001%-0.005%, and the rest is Mg; the pumice iron oxide cobalt composite is iron oxide cobalt drilled into the pores of the pumice, and forms a film with a thickness of 0.1-10μm on the pore wall.

2, a kind of preparation method of magnesium alloy base pumice iron oxide cobalt composite material, it is characterized in that: it comprises the following steps:

a. Preparation of pumice iron oxide cobalt compound: put ferric chloride, cobalt chloride and ferrous ammonium sulfate into a hydrothermal container with Teflon lining, add water to dissolve (add a small amount of water until dissolved), Pack pumice again, pumice particle size is 0.5-1mm, stir above three kinds of materials and reach 2-7min, the weight ratio of four kinds of material ferric chloride, cobalt chloride, ferrous ammonium sulfate and pumice is 1: (1-2 ): 1: (1-2), after the stirring is finished, place the stirred material in an oven at 220° C. for 3 hours and then cool naturally to obtain the pumice iron oxide cobalt compound;

Then dolomite and pumice iron oxide cobalt compound are mixed, the size of dolomite particle is 0.01-0.06mm, the weight ratio of pumice iron oxide cobalt compound and dolomite is 1: 0.05-0.09, the dolomite and pumice iron oxide cobalt compound Put the mixture of the compound into the cavity of the steel mold with the bottom vacuum system of the heating device to form a composite prefabricated body, and control the composite prefabricated body to account for 40-45% of the metal mold cavity volume; open the mold heating device, control 520-540°C inside the steel mold;

b. Preparation of magnesium alloy solution: the weight percentage is 4% to 8% for Al, 0.01% to 0.05% for Th, 0.5% to 1% for Si, 0.001% to 0.005% for Bi, and the rest is Mg Raw materials are melted into alloy liquid at 1680-1720°C;

c. Turn on the vacuum system, control the relative vacuum in the above-mentioned steel mold to be -30Kpa, pour the above-mentioned magnesium alloy liquid into the composite prefabricated body in the cavity of the steel mold, and fill the mold, the magnesium alloy liquid is in the Under the pressure of relative vacuum degree of -30Kpa, infiltrate into the gap in the dolomite and pumice iron oxide cobalt composite preform, turn off the mold heating device, and the alloy liquid is cooled and solidified in the mold to form a magnesium alloy-based pumice iron oxide cobalt composite material.

The beneficial effects of the present invention compared with prior art are as follows:

In the present invention, the pumice stone has large voids and is easy to accept ferrite. The ferrite is in the voids of the pumice stone to form a pumice iron oxide-cobalt composite that the ferrite will not scatter, thus becoming a solid material center for the composite material to absorb electromagnetic waves; iron Combined with cobalt oxide to absorb waves, the effect is stronger than that of single ferrite.

The pumice iron oxide cobalt composite is that iron cobalt oxide drills into the pores of the pumice and forms a film with a thickness of 0.1-10 μm on the wall of the pores. The iron cobalt oxide in the pumice iron oxide cobalt compound is a mixture of Fe ₃ O ₄ and CO ₂ O ₃ .

The ferrite is in the void of the pumice and is not in contact with the magnesium alloy liquid, so it will not cause oxidation of the magnesium alloy;

The chemical composition of dolomite is CaMg[CO ₃ ] ₂ . The function of dolomite is to separate the pumice particles in the composite material, so that the magnesium alloy liquid can penetrate into the gap between the pumice particles. At the same time, the dolomite has the function of damping vibration.

Si and Bi in magnesium alloy can promote the interfacial bonding between magnesium alloy and pumice. Th in the magnesium alloy can reduce the particle size of the magnesium alloy and increase the strength of the matrix of the composite material. Robust pumice-iron oxide-cobalt composites enhance compressive properties of magnesium alloy composites. These can improve the mechanical properties of magnesium alloy-based pumice iron oxide cobalt composites.

The properties of the alloy of the present invention are shown in Table 1.

The pumice stone has large voids and is easy to accept ferrite, so the stirring and heating time in the preparation are short, and the production cycle is short.

The preparation process of the composite material is simple, and the produced composite material has a certain good damping performance and superior wave-absorbing performance, and the production cost is low, which is very convenient for industrial production.

4. Description of drawings

Fig. 1 is the metallographic structure of the magnesium alloy-based pumice iron oxide-cobalt composite material prepared in Example 1 of the present invention.

It can be seen from Figure 1 that there are pumice iron oxide cobalt complexes distributed on the magnesium alloy matrix.

5. Specific implementation

The following examples are only used to illustrate the present invention, and the weight percentages can be replaced by weight g, kg or other weight units.

Embodiment one:

The preparation process of magnesium alloy base pumice iron oxide cobalt composite material of the present invention is as follows:

a. Preparation of pumice iron oxide cobalt compound: put ferric chloride, cobalt chloride and ferrous ammonium sulfate into a hydrothermal container with Teflon lining, add water to dissolve, and then load pumice, the size of pumice particles It is about 0.5mm. Stir the above three substances for 2-7min. The weight ratio of the four substances, ferric chloride, cobalt chloride, ferrous ammonium sulfate and pumice, is 1:1:1:1. After heat preservation in an oven at 220°C for 3 hours, cool naturally to obtain the pumice iron oxide cobalt compound;

Then dolomite and pumice iron oxide cobalt compound are mixed, the size of dolomite particle is about 0.01mm, the weight ratio of pumice iron oxide cobalt compound and dolomite is 1: 0.05, the mixture of dolomite and pumice iron oxide cobalt compound Put it into the cavity of a steel mold with a bottom vacuum system with a heating device to form a composite prefabricated body, and control the composite prefabricated body to account for 45% of the metal mold cavity volume; turn on the heating device, and control the temperature in the steel mold to 520 -540°C;

B, the preparation of magnesium alloy liquid: be 4% by weight percentage Al, Th is 0.01%, Si is 0.5%, Bi is the raw material of 0.001%, is melted into alloy liquid at 1680-1720 ℃ of temperature;

c. Turn on the vacuum system, control the relative vacuum in the above-mentioned steel mold to be -30Kpa, pour the above-mentioned magnesium alloy liquid into the composite prefabricated body in the cavity of the steel mold, and fill the mold, the magnesium alloy liquid is in the Under the action of vacuum pressure, it penetrates into the gap of the dolomite and pumice iron oxide cobalt composite prefabricated body, closes the mold heating device, and the alloy liquid cools and solidifies in the mold to form a magnesium alloy-based pumice iron oxide cobalt composite material.

Embodiment two:

a. Preparation of the pumice iron oxide-cobalt complex: when forming the pumice iron oxide-cobalt complex, the weight ratio of ferric chloride, cobalt chloride, ferrous ammonium sulfate and pumice is 1:2:1:2. The pumice particle size is about 1mm.

Composite preform: in the mixture of dolomite and pumice iron oxide cobalt compound, the weight ratio of pumice iron oxide cobalt compound to dolomite is 1:0.09, and the size of dolomite particles is 0.06mm; control the pumice iron oxide cobalt compound The volume percentage of the composite material is 40%;

B, the preparation of magnesium alloy liquid: the weight percent of the chemical composition of this magnesium alloy substrate: Al is 8%, Th is 0.05%, Si is 1%, Bi is 0.005%;

Its preparation process is with embodiment one.

Embodiment three:

a. Preparation of the pumice iron oxide-cobalt complex: when forming the pumice iron oxide-cobalt complex, the weight ratio of ferric chloride, cobalt chloride, ferrous ammonium sulfate and pumice is 1:1.2:1:1.2. The pumice particle size is about 0.6mm.

Composite preform: in the mixture of dolomite and pumice iron oxide cobalt compound, the weight ratio of pumice iron oxide cobalt compound to dolomite is 1:0.07, and the size of dolomite particles is 0.05mm; control the pumice iron oxide cobalt compound The volume percentage of the composite material is 43%;

B, the preparation of magnesium alloy liquid: the weight percent of the chemical composition of this magnesium alloy substrate: Al is 6%, Th is 0.04%, Si is 0.7%, Bi is 0.003%;

Its preparation process is with embodiment one.

Embodiment four: (raw material proportioning is not the example within the proportioning scope of the present invention)

a. Preparation of the pumice iron oxide-cobalt complex: when forming the pumice iron oxide-cobalt complex, the weight ratio of ferric chloride, cobalt chloride, ammonium ferrous sulfate and pumice is 1:0.8:1:0.7. The pumice particle size is 0.4 mm.

Composite preform: in the mixture of dolomite and pumice iron oxide cobalt compound, the weight ratio of pumice iron oxide cobalt compound to dolomite is 1:0.05-0.09, and the size of dolomite particles is 0.005mm; control pumice iron oxide cobalt The composite accounts for 40% by volume of the composite material;

B, the preparation of magnesium alloy liquid: the weight percent of the chemical composition of this magnesium alloy substrate: Al is 3%, Th is 0.008%, Si is 0.3%, Bi is 0.0007%;

Its preparation process is with embodiment one.

Embodiment five: (raw material proportioning is not the example within the proportioning scope of the present invention)

a. Preparation of the pumice iron oxide-cobalt complex: when forming the pumice iron oxide-cobalt complex, the weight ratio of ferric chloride, cobalt chloride, ammonium ferrous sulfate and pumice is 1:2.5:1:2.1. The particles of the pumice iron oxide cobalt complex are 1.2mm.

Composite preform: in the mixture of dolomite and pumice iron oxide cobalt compound, the weight ratio of pumice iron oxide cobalt compound to dolomite is 1:0.2, and the size of dolomite particles is 0.8mm; control the pumice iron oxide cobalt compound The volume percentage of the composite material is 45%;

b. Preparation of magnesium alloy liquid: the weight percent of the chemical composition of the magnesium alloy matrix: Al is 9%, Th is 0.07%, Si is 1.3%, and Bi is 0.007%.

Its preparation process is with embodiment one.

The following table is a comparison table of alloy properties with different components and proportions:

Table 1

Magnesium alloy-based pumice iron oxide cobalt composite material, the particle size of the composite is too small, which not only reduces the absorbing unit, reduces the absorbing strength and vibration damping strength, but is not conducive to the manufacture of composite materials; the particle size of the composite If the size is too large, the wave-absorbing unit increases, which reduces the number of wave-absorbing units per unit volume of the composite material, and is not conducive to wave absorption and vibration reduction.

When the magnesium alloy-based pumice iron oxide cobalt composite material is prepared, the number of pumice stones is too small, and it is difficult for ferric chloride, cobalt chloride, and ferrous ammonium sulfate to all enter the gap between the pumice stones. The total amount of iron oxide in the composite material is small, and the absorbing strength is weak; If the quantity is too much, it is difficult to form a perfect composite material, and the amount of iron oxide contained in the gap of the pumice stone is small, and the absorbing strength is also weak.

When preparing magnesium alloy-based pumice iron oxide cobalt composites, the amount of dolomite is too small or the dolomite particles are too small to separate the pumice particles, which is not conducive to the infiltration of magnesium alloy liquid. The amount of dolomite is too large or the dolomite particles are too large , will affect the mechanical properties of magnesium alloy-based pumice iron oxide cobalt composites.

Al, Th, Si, Bi in the magnesium alloy matrix are within the scope of this application, and the composite material has good properties. These elements exceed the ratio range of the present application, the amount of brittle compounds is large, the magnesium alloy is difficult to combine with the pumice interface, the mechanical properties of the titanium alloy itself are reduced, and the wave absorption and vibration damping properties of the composite material are also greatly reduced.

Claims (2)

1. A magnesium alloy-based pumice iron oxide cobalt composite material, the composite material is based on magnesium alloy, on the substrate is distributed with pumice iron oxide cobalt compound and dolomite particles, pumice iron oxide cobalt compound and dolomite particle two The volume percentage of the composite material is 40-45%; the size of the composite particles is 0.5-1mm; the weight percentage of the chemical composition of the magnesium alloy matrix: Al is 4%-8%, Th is 0.01%-0.05% , Si is 0.5%-1%, Bi is 0.001%-0.005%, and the rest is Mg. 2. A preparation method for a magnesium alloy-based pumice iron oxide cobalt composite material, characterized in that: it may further comprise the steps: a, the preparation of pumice iron oxide cobalt compound: put ferric chloride, cobalt chloride and ammonium ferrous sulfate into the hydrothermal container with polytetrafluoroethylene lining, add water to dissolve, then pack pumice stone, the particle size of pumice stone is 0.5-1mm, stir the above three substances for 2-7min, the weight ratio of the four substances ferric chloride, cobalt chloride, ferrous ammonium sulfate and pumice is 1: (1-2): 1: (1-2) , after the stirring is completed, place the stirring material in an oven at 220°C for 3 hours and then cool naturally to obtain the pumice iron oxide cobalt compound; Then dolomite and pumice iron oxide cobalt compound are mixed, the size of dolomite particle is 0.01-0.06mm, the weight ratio of pumice iron oxide cobalt compound and dolomite is 1: 0.05-0.09, the dolomite and pumice iron oxide cobalt compound Put the mixture of the compound into the cavity of the steel mold with the bottom vacuum system of the heating device to form a composite prefabricated body, and control the composite prefabricated body to account for 40-45% of the metal mold cavity volume; open the mold heating device, control 520-540°C inside the steel mold; b. Preparation of magnesium alloy solution: the weight percentage is 4% to 8% for Al, 0.01% to 0.05% for Th, 0.5% to 1% for Si, 0.001% to 0.005% for Bi, and the rest is Mg Raw materials are melted into alloy liquid at 1680-1720°C; c. Turn on the vacuum system, control the relative vacuum in the above-mentioned steel mold to be -30Kpa, pour the above-mentioned magnesium alloy liquid into the composite prefabricated body in the cavity of the steel mold, and fill the mold, the magnesium alloy liquid is in the Under the pressure of relative vacuum degree of -30Kpa, infiltrate into the gap in the dolomite and pumice iron oxide cobalt composite preform, turn off the mold heating device, and the alloy liquid is cooled and solidified in the mold to form a magnesium alloy-based pumice iron oxide cobalt composite material.

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