CN104294071A - A kind of low-temperature glass phase reinforced SiCp/Cu composite material and preparation method thereof - Google Patents

Abstract

The invention discloses a low-temperature glass-phase reinforced _SiCp /Cu composite material and a preparation method thereof, belonging to the technical field of preparation of ceramic-reinforced metal matrix composite materials. In the Cu matrix of the SiC _p /Cu composite material, SiC particles wrapped by the glass phase are dispersed, and the glass phase components are SiO ₂ and K ₂ O, wherein the molar ratio of SiO ₂ to K ₂ O is 2-6, and the SiC and K 2 O The volume ratio of SiO ₂ and Cu in the glass phase is 1:(0.2~1.2):(2~4). On the one hand, the low-temperature glass phase has good interfacial wettability with SiC particles during melting, and at the same time, a certain amount of Cu ₂ O will be formed on the surface of the Cu matrix particles during the sintering process of the composite material, which will participate in the formation of the interface glass phase, so the Cu matrix On the other hand, the introduction of the interface glass phase can avoid direct surface contact when multiple SiC particles are agglomerated, and at the same time prevent the interdiffusion of reactant atoms in the interfacial solid phase reaction, thereby effectively inhibiting the interfacial solid phase reaction products Formation, so that the composite material can obtain good comprehensive mechanical properties.

Description

A kind of low-temperature glass phase reinforced SiCp/Cu composite material and preparation method thereof

technical field

The invention specifically relates to a low-temperature glass-phase reinforced _SiCp /Cu composite material and a preparation method of the composite material, belonging to the technical field of preparation of ceramic-reinforced metal matrix composite materials.

Background technique

Silicon carbide particle-reinforced copper-based composite material combines the respective advantages of copper matrix and silicon carbide-reinforced particles, synergistically complements each other, combines excellent electrical conductivity, thermal conductivity, and wear resistance, and has the advantages of low raw material cost and simple preparation process. SiC _p /Cu composite material is likely to become a new generation of structure-function integrated high-performance materials, and play an important role in aerospace, electronic packaging and other fields. It is a new type of material with broad application prospects. However, due to the difference in the lattice types of SiC and Cu, there are a series of problems such as non-wetting and poor dispersion uniformity between the molten Cu and SiC phases, and interfacial reactions are prone to occur during the sintering process of the composite material, which seriously affects the SiC _p /Cu composite performance improvement. At present, there are a large number of literature studies on the interface modification of ceramic-metal composites to improve the interface bonding and dispersion uniformity of the silicon carbide particle reinforcement phase and the metal matrix, but the overall performance improvement is relatively limited.

Contents of the invention

The purpose of the present invention is to provide a SiC _p /Cu composite material reinforced by low temperature glass phase.

At the same time, the invention also provides a preparation method of _SiCp /Cu composite material reinforced by low-temperature glass phase.

In order to achieve the above object, the technical solution adopted in the present invention is:

A _SiCp /Cu composite material reinforced by a low-temperature glass phase, in which SiC particles wrapped by a glass phase are dispersed in a Cu matrix.

The glass phase components are SiO ₂ and K ₂ O, and the molar ratio of SiO ₂ to K ₂ O is 2-6.

The volume ratio of SiC to SiO ₂ and Cu in the glass phase is 1:(0.2-1.2):(2-4).

The size of the SiC particles is 3-20 μm.

A kind of preparation method of _SiCp /Cu composite material reinforced by low-temperature glass phase, comprises the following steps:

(1) The composite gel body of SiC wrapped by amorphous SiO ₂ was prepared by sol-gel method, and the powder of SiC wrapped by amorphous SiO ₂ was obtained by suction filtration, drying and grinding;

(2) Grinding and mixing the powder in step (1) with K ₂ CO ₃ 1/2H ₂ O, pressing into tablets and calcining to form a glass phase, grinding and sieving to obtain a powder of SiC wrapped in the glass phase;

(3) Coating Cu particles on the surface of the powder particles in step (2) by means of displacement reduction reaction, suction filtration, drying and sieving to obtain SiC _p /Cu composite powder;

(4) Take the composite powder in step (3), and prepare SiC _p /Cu composite material reinforced by low temperature glass phase by vacuum hot pressing sintering method.

The sol-gel method in the step (1) is as follows: disperse tetraethyl orthosilicate (TEOS) and α-SiC in ethanol solution, adjust the pH of the solution to 2-3, fully Stir to completely hydrolyze the tetraethyl orthosilicate to form a SiO ₂ sol, then adjust the pH value of the solution to 8-11, and stir to obtain a composite gel. The stirring time under acidic conditions is 2-6 hours, and the stirring time under alkaline conditions is 0.1-1 hour.

In the step (1), after vacuum filtration, air blast drying is performed at 75-85° C. for 1.5-2.5 hours.

The molar ratio of SiO ₂ to K ₂ CO ₃ ·1/2H ₂ O in the powder in step (1) in the step (2) is 2-6.

The pressure for tablet forming in the step (2) is 5-20 MPa.

The calcining temperature in the step (2) is 750-800° C., and the calcining time is 1-4 hours.

The sieving in the step (2) is to pass through a 200-mesh sieve.

The replacement and reduction reaction in the step (3) is: disperse the powder in the step (2) in the soluble copper salt solution, add the suspension containing the reducing metal powder while stirring at 0-10°C, and replace the copper .

The soluble copper salt is copper sulfate, copper chloride or copper nitrate.

The reducing metal powder is preferably zinc powder or iron powder.

After suction filtration in the step (3), vacuum-dry at 75-85°C for 5-7 hours, pass through a 120-mesh sieve, and pass through a sieve at least three times.

The vacuum hot-pressing sintering method in the step (4) is: pre-press the composite powder in the step (3) at room temperature and a pressure of 5-15 MPa, raise the temperature to 550-650°C for 10-30 minutes, and then Boost the pressure to 20-40MPa, raise the temperature to 700-800°C and hold the pressure for 0.5-2 hours, then release the mold after cooling with the furnace temperature.

Beneficial effects of the present invention:

The invention uses a three-step wrapping method to prepare _SiCp /Cu composite powder, and then vacuum hot-pressing sinters to prepare composite materials. By wrapping the low-temperature glass phase on the surface of SiC particles as an interface layer, the interface bonding characteristics of _SiCp /Cu composite materials can be effectively improved. , which controls the interface response. On the one hand, the low-temperature glass phase has good interfacial wettability with SiC particles during melting, and at the same time, a certain amount of Cu ₂ O will be formed on the surface of the Cu matrix particles during the sintering process of the composite material, which will participate in the formation of the interface glass phase, so the Cu matrix On the other hand, the introduction of the interface glass phase can avoid direct surface contact when multiple SiC particles are agglomerated, and at the same time prevent the interdiffusion of reactant atoms in the interfacial solid-state reaction, thereby effectively inhibiting its interfacial solid-state reaction The product - the formation of brittle copper silicides, enables the composite material to obtain good comprehensive mechanical properties.

Description of drawings

Fig. 1 is the XRD pattern of SiO ₂ (a) and glass phase (b) wrapped on the surface of SiC particles in Example 1 of the present invention;

Fig. 2 is the SEM picture of SiC particle in embodiment 1 through different wrapping steps;

Fig. 3 is the cross-sectional SEM figure of _SiCp /Cu composite material in embodiment 1;

FIG. 4 is the XRD pattern of the SiC _p /Cu composite material in Example 1.

Detailed ways

The following examples only illustrate the present invention in further detail, but do not constitute any limitation to the present invention.

Example 1

The SiC _p /Cu composite material reinforced by low temperature glass phase in this example has SiC particles wrapped by glass phase dispersed in the Cu matrix, wherein the volume ratio of SiC, SiO ₂ and Cu is 1:0.6:3, and the glass The molar ratio of _SiO2 to _K2O in the phase is 3, and the size of SiC particles is 10 μm.

The preparation method of the _SiCp /Cu composite material reinforced by the low-temperature glass phase in this embodiment comprises the following steps:

(1) According to the volume ratio of ester, alcohol and water as 23:35:3, disperse tetraethyl orthosilicate (TEOS) and α-SiC in ethanol solution, adjust the pH of the solution to 2 with citric acid, Stir magnetically at 45°C for 3 hours to completely hydrolyze tetraethyl orthosilicate into SiO ₂ to form a sol, then adjust the pH of the solution to 8 with ammonia water, continue magnetically stirring for 0.1 hour to obtain a composite gel, vacuum filter, and Blast drying at 80°C for 2 hours, and grinding to obtain SiC powder coated with amorphous SiO ₂ ;

(2) Grinding and mixing the powder in step (1) with K ₂ CO ₃ ·1/2H ₂ O, the molar ratio of SiO ₂ and K ₂ CO ₃ ·1/2H ₂ O in the powder is 3, and the pressure is 10MPa Forming a sheet, calcining at 750°C for 4 hours to generate a glass phase, grinding the powder, and passing through a 200-mesh sieve to obtain a powder consisting of a glass phase including SiC;

(3) Disperse the powder in step (2) in the copper sulfate solution, add the suspension containing reducing zinc powder dropwise while stirring at 0°C, replace the copper, and use the rotation to precipitate the powder in step (2) Coating Cu particles on the surface of the bulk particles, suction filtration, vacuum drying at 80°C for 6 hours, and passing through a 120-mesh sieve three times to obtain SiC _p /Cu composite powder;

(4) Pre-press the composite powder in step (3) at room temperature and 10MPa pressure, raise the temperature to 600°C at 20°C/min, keep the temperature and pressure for 20 minutes, then increase the pressure to 30MPa, and heat up to 750°C for heat preservation and pressure After 1 hour, the SiC _p /Cu composite material was obtained after demolding after cooling with the furnace temperature.

In this example, the XRD patterns of SiO ₂ (a) and glass phase (b) coated on the surface of SiC particles are shown in Figure 1; ) SiC wrapped in amorphous SiO ₂ , (c) SiC wrapped in glass phase, (d) SiC _p /Cu; the cross-sectional SEM image of the SiC _p /Cu composite is shown in Figure 3; the XRD pattern of the SiC _p /Cu composite is shown in Figure 4.

It can be seen from FIG. 3 that the SiC _p /Cu composite material prepared in this example has uniform structure and high density. The porosity is 0.99-2.22%, the Vickers hardness is 1.93-2.07GPa, and the bending strength is 228-242MPa.

Example 2

The SiC _p /Cu composite material reinforced by low temperature glass phase in this example has SiC particles wrapped by glass phase dispersed in the Cu matrix, wherein the volume ratio of SiC, SiO ₂ and Cu is 1:0.2:2, and the glass The molar ratio of _SiO2 to _K2O in the phase is 2, and the size of SiC particles is 10 μm.

The preparation method of the _SiCp /Cu composite material reinforced by the low-temperature glass phase in this embodiment comprises the following steps:

(1) According to the volume ratio of ester, alcohol and water as 23:35:3, disperse tetraethyl orthosilicate (TEOS) and α-SiC in ethanol solution, adjust the pH of the solution to 2 with citric acid, Stir magnetically at 30°C for 6 hours to completely hydrolyze tetraethyl orthosilicate to SiO ₂ to form a sol, then adjust the pH value of the solution to 9 with ammonia water, continue magnetic stirring for 1 hour to obtain a composite gel, and vacuum filter it at 75 Blast drying at ℃ for 2.5 hours, and grinding to obtain SiC powder coated with amorphous SiO ₂ ;

(2) Grinding and mixing the powder in step (1) with K ₂ CO ₃ ·1/2H ₂ O, the molar ratio of SiO ₂ and K ₂ CO ₃ ·1/2H ₂ O in the powder is 2, and the pressure is 10MPa Forming a sheet, calcining at 800°C for 1 hour to generate a glass phase, grinding the powder, and passing through a 200-mesh sieve to obtain a powder consisting of a glass phase including SiC;

(3) Disperse the powder in step (2) in the copper sulfate solution, add the suspension containing reducing zinc powder dropwise while stirring at 10°C, replace the copper, and use the rotation to precipitate the powder in step (2) Coating Cu particles on the surface of the bulk particles, suction filtration, vacuum drying at 75°C for 7 hours, and passing through a 120-mesh sieve three times to obtain SiC _p /Cu composite powder;

(4) Pre-press the composite powder in step (3) at room temperature and 15MPa pressure, raise the temperature to 550°C at 20°C/min, keep the temperature and pressure for 30 minutes, then increase the pressure to 40MPa, and raise the temperature to 800°C for heat preservation and pressure After 0.5 hours, the SiC _p /Cu composite material is obtained after demolding after cooling with the furnace temperature.

In this embodiment, the porosity of the SiC _p /Cu composite material is 2.41-4.74%, the Vickers hardness is 1.66-1.88 GPa, and the bending strength is 220-235 MPa.

Example 3

In this example, the _SiCp /Cu composite material reinforced by the low-temperature glass phase is dispersed in the Cu matrix with SiC particles wrapped by the glass phase, wherein the volume ratio of SiC, SiO ₂ , and Cu is 1:1.2:4, and the glass The molar ratio of _SiO2 to _K2O in the phase is 6, and the size of the SiC particles is 10 μm.

The preparation method of the _SiCp /Cu composite material reinforced by the low-temperature glass phase in this embodiment comprises the following steps:

(1) According to the volume ratio of ester, alcohol and water as 23:35:3, disperse tetraethyl orthosilicate (TEOS) and α-SiC in ethanol solution, adjust the pH of the solution to 3 with citric acid, Stir magnetically at 60°C for 2 hours to completely hydrolyze tetraethyl orthosilicate into SiO ₂ to form a sol, then adjust the pH value of the solution to 11 with ammonia water, continue magnetic stirring for 2 hours to obtain a composite gel, vacuum filter, and obtain a composite gel at 85 Blow drying at ℃ for 1.5 hours, and grind to obtain SiC powder wrapped with amorphous SiO ₂ ;

(2) Grinding and mixing the powder in step (1) with K ₂ CO ₃ ·1/2H ₂ O, the molar ratio of SiO ₂ and K ₂ CO ₃ ·1/2H ₂ O in the powder is 6, and the pressure is 20MPa Forming a sheet, calcining at 760°C for 3 hours to generate a glass phase, grinding the powder, and passing through a 200-mesh sieve to obtain a powder consisting of a glass phase including SiC;

(3) Disperse the powder in step (2) in the copper sulfate solution, add the suspension containing reducing zinc powder dropwise while stirring at 5°C, replace the copper, and use the rotation to precipitate the powder in step (2) Coating Cu particles on the surface of the bulk particles, suction filtration, vacuum drying at 85°C for 5 hours, and passing through a 120-mesh sieve three times to obtain SiC _p /Cu composite powder;

(4) Pre-press the composite powder in step (3) at room temperature and 5MPa pressure, raise the temperature to 650°C at 20°C/min, keep the temperature and pressure for 10 minutes, then increase the pressure to 20MPa, and heat up to 700°C for heat preservation and pressure After 2 hours, the SiC _p /Cu composite material was obtained after demolding after cooling with the furnace temperature.

The porosity of the SiC _p /Cu composite material in this embodiment is 4.46-6.15%, the Vickers hardness is 1.58-1.69 GPa, and the bending strength is 172-186 MPa.

Claims (10)

1. the SiC that strengthens mutually of a low temperature glass _p/ Cu matrix material, is characterized in that: in Cu matrix, be dispersed with the SiC particle wrapped up by glassy phase.

2. the SiC that strengthens mutually of low temperature glass according to claim 1 _p/ Cu matrix material, is characterized in that: described glassy phase composition is SiO ₂and K ₂o, SiO ₂with K ₂the mol ratio of O is 2 ~ 6.

3. the SiC that strengthens mutually of low temperature glass according to claim 2 _p/ Cu matrix material, is characterized in that: SiO in described SiC and glassy phase ₂and the volume ratio of Cu is 1:(0.2 ~ 1.2): (2 ~ 4).

4. the SiC that strengthens mutually of the low temperature glass as described in any one of claim 1-3 _pthe preparation method of/Cu matrix material, is characterized in that: comprise the following steps:

(1) adopt sol-gel method preparation by amorphous Si O ₂the plural gel body of parcel SiC, suction filtration, dry rear grinding obtain by amorphous Si O ₂the powder of parcel SiC;

(2) by the powder of step (1) and K ₂cO ₃1/2H ₂o ground and mixed, after compression molding, calcining generates glassy phase, grind, sieve after obtain wrapping up the powder of SiC by glassy phase;

(3) utilize displacement reduction reaction in the powder granule surface parcel Cu particle of step (2), sieve after suction filtration, drying and obtain SiC _p/ Cu composite granule;

(4) get the composite granule of step (3), utilize the SiC that vacuum heating-press sintering legal system strengthens mutually for low temperature glass _p/ Cu matrix material.

5. the SiC that strengthens mutually of low temperature glass according to claim 4 _pthe preparation method of/Cu matrix material, it is characterized in that: the sol-gel method in described step (1) is: tetraethoxy (TEOS), α-SiC are scattered in ethanolic soln, regulator solution pH value is 2 ~ 3, stir at 30 ~ 60 DEG C, regulator solution pH value is 8 ~ 11 again, stirs and obtain plural gel body.

6. the SiC that strengthens mutually of low temperature glass according to claim 4 _pthe preparation method of/Cu matrix material, is characterized in that: in described step (2), the temperature of calcining is 750 ~ 800 DEG C, and calcination time is 1 ~ 4 hour.

7. the SiC that strengthens mutually of low temperature glass according to claim 4 _pthe preparation method of/Cu matrix material, is characterized in that: the displacement reduction reaction in described step (3) is: be scattered in soluble copper salts solution by the powder of step (2), add the suspension liquid containing reducing metal powder while stirring, displacement copper.

8. the SiC that strengthens mutually of low temperature glass according to claim 7 _pthe preparation method of/Cu matrix material, is characterized in that: described soluble copper salt is copper sulfate, cupric chloride or cupric nitrate.

9. the SiC that strengthens mutually of low temperature glass according to claim 7 _pthe preparation method of/Cu matrix material, is characterized in that: described reducing metal powder is zinc powder or iron powder.

10. the SiC that strengthens mutually of low temperature glass according to claim 4 _pthe preparation method of/Cu matrix material, it is characterized in that: the vacuum heating-press sintering method in described step (4) is: by the precompressed under normal temperature, 5 ~ 15MPa pressure of the composite granule of step (3), be warming up to 550 ~ 650 DEG C of heat-insulation pressure keepings 10 ~ 30 minutes, boost to 20 ~ 40MPa again, be warming up to 700 ~ 800 DEG C of heat-insulation pressure keepings 0.5 ~ 2 hour, with the demoulding after furnace temperature cooling.