Preparation method of 4j50-cnts / cu composite wire for electronic packaging

Abstract

The application discloses a kind of preparation methods of 4J50-CNTs / Cu composite wire for electronic packaging, comprising the following steps: one, carbon nanotube powder is dispersed, to obtain precursor liquid;Two, Cu (NO3) 2 and tween are added to precursor liquid, to obtain mixed precursor liquid;Three, ammonia is added in mixed precursor liquid, to obtain reaction liquid;Four, the reaction liquid is filtered, to obtain oxidized carbon nanotube / copper oxide powder;Five, the powder is reduced, to obtain surface modified carbon nanotube composite powder;Six, the composite powder is sintered, to obtain composite bar;Seven, composite bar and sheath hydraulic pressure expansion, to obtain composite ingot;Eight, the composite ingot is cold isostatic pressing and hot extrusion, to obtain extruded bar blank;Nine, the extruded bar blank is drawn in multiple passes, to obtain composite wire.The wire of the application significantly improves the strength and the electrically conductive and thermally conductive performance under the premise of ensuring not to sacrifice its original air tightness and low expansion coefficient, and lays a foundation for the development of high-performance electronic components.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electronic packaging, and particularly relates to a preparation method of 4J50-CNTs / Cu composite wire for electronic packaging. BACKGROUND

[0002] With the gradual improvement of China's electronic information construction and national defense strength, the demand for various electronic components is increasingly prominent, and the demand for import substitution of high-performance electronic components is continuously increasing. Metal lead is widely used in electronic packaging fields such as relays, connectors, integrated circuit housings, and is a key material for realizing large load and miniaturization of electronic products. The performance of packaging materials is the key to improving the packaging effect, which requires the packaging materials to have low thermal expansion coefficient and good air tightness. The expansion coefficient of Fe-Ni series 4J50 constant expansion alloy (kovar alloy) is basically consistent with that of soft glass, which is commonly used as a sealing alloy. Copper has good electrical conductivity and thermal conductivity, and the 4J50 / Cu composite wire prepared by taking copper as the core material and coating steel outside using the layered coating preparation technology has the electrical conductivity and thermal conductivity of copper and is commonly used as an electronic component packaging lead. With the continuous widening of the electronic packaging field and the rapid growth of its demand, higher requirements are put forward for the performance of the 4J50 / Cu composite wire, which requires not only low thermal expansion coefficient and good air tightness, but also high strength and good electrical conductivity and thermal conductivity. Therefore, it is urgent to develop new preparation technologies and find new doping sources to improve the comprehensive performance of the composite material.

[0003] Carbon nanotubes (CNTs) are one-dimensional quantum materials curled around the central axis by single or multiple layers of graphene layers at a certain spiral angle. Due to its high thermal conductivity, high carrier mobility and high strength, it has become an ideal reinforcing phase of metal matrix composites. The introduction of CNTs reinforcing phase into the copper core of 4J50 / Cu composite wire is expected to realize the synergistic strengthening of the strength and electrical conductivity of the composite wire while ensuring its low expansion coefficient. However, due to the easy agglomeration of CNTs and the poor bonding strength of the CNTs / copper interface, the performance of the CNTs / Cu composite material is far from the expected value. Therefore, how to realize the uniform dispersion of CNTs in the copper core of 4J50 / Cu composite wire and how to improve the bonding strength of the carbon nanotube / copper composite interface have become the main research direction. SUMMARY

[0004] The technical problems to be solved by the present application are to provide a preparation method of 4J50-CNTs / Cu composite wire for electronic packaging in view of the above-mentioned deficiencies of the prior art.

[0005] To solve the above technical problems, the technical scheme adopted by the present application is as follows: a preparation method of 4J50-CNTs / Cu composite wire for electronic packaging, characterized in that the method comprises the following steps:

[0006] Step one: carbon nanotube powder is added to deionized water, and then ultrasonic dispersion is carried out to obtain a precursor solution;

[0007] Step two: Cu(NO3)2 solution and Tween are sequentially added to the precursor solution obtained in step one, and then stirring and dispersion are carried out, followed by heating and stirring to obtain a mixed precursor solution;

[0008] Step three: under the condition of heating and stirring, ammonia solution is slowly added dropwise to the mixed precursor solution obtained in step two, and then constant temperature stirring is carried out to obtain a reaction solution;

[0009] Step four: the reaction solution obtained in step three is filtered, and then the filtered product is washed with deionized water for multiple times and freeze-dried to obtain oxidized carbon nanotube / copper oxide powder;

[0010] Step five: the oxidized carbon nanotube / copper oxide powder obtained in step four is heated and reduced in H2-Ar atmosphere to obtain surface-modified carbon nanotube composite powder;

[0011] Step six: the surface-modified carbon nanotube composite powder obtained in step five is loaded into a graphite mold, and then discharge plasma sintering is carried out to obtain a composite rod;

[0012] Step seven: the composite rod obtained in step six and 4J50 are subjected to pickling and drying, and then the dried composite rod is loaded into the dried 4J50, and then is placed under a hydraulic press for hydraulic pressure expansion to obtain a composite ingot;

[0013] Step eight: the composite ingot obtained in step seven is subjected to cold isostatic pressing to obtain a formed piece, and then is subjected to hot extrusion processing to obtain an extruded rod blank;

[0014] Step nine: the extruded rod blank obtained in step eight is subjected to multi-pass drawing to obtain 4J50-CNTs / Cu composite wire.

[0015] The present application adds carbon nanotube powder after ultrasonic dispersion into Cu(NO3)2 solution and Tween, stirs uniformly, then slowly adds ammonia solution as a reducing agent under heating and stirring, copper ions in the reaction solution and functional groups on the surface of carbon nanotube are adsorbed on the surface of carbon nanotube by Coulomb force between different charges, through filtration and freeze drying, loose powder is ensured to prevent carbon nanotube stacking, and oxidized carbon nanotube / oxidized copper powder is obtained, through heating reduction of oxidized carbon nanotube / oxidized copper powder in H2-Ar atmosphere, a large amount of oxide existing will seriously weaken the conductivity of the matrix, so it is necessary to carry out reduction heat treatment, and after reduction, surface modified carbon nanotube composite powder is obtained, through spark plasma sintering, a composite rod, i.e. the core material of the composite wire, is obtained, the composite rod after drying is loaded into a dried 4J50 package, then liquid pressure expansion, cold isostatic pressing, hot extrusion, multi-pass drawing and high vacuum annealing are carried out to strengthen the bonding performance of the composite interface, and 4J50-CNTs / Cu composite wires of different size specifications are obtained.

[0016] The preparation method of the 4J50-CNTs / Cu composite wire for electronic packaging has the characteristics that in step one, the mass of the carbon nanotube powder and the volume of the deionized water are in the ratio of 1-1.6:200, wherein the unit of mass is g and the unit of volume is mL; and the ultrasonic dispersion time is greater than 20 min. The present application controls the mass of the carbon nanotube powder and the volume of the deionized water and the ultrasonic dispersion time to ensure that the carbon nanotube is uniformly dispersed in the solvent.

[0017] The preparation method of the 4J50-CNTs / Cu composite wire for electronic packaging has the characteristics that in step two, the volume of the Cu(NO3)2 solution, the mass of the Tween and the mass of the carbon nanotube powder in step one are in the ratio of 1000-1100:0.5-1:1-1.6, wherein the unit of mass is g and the unit of volume is mL; the concentration of the Cu(NO3)2 solution is 0.12 g / mL-0.40 g / mL; the stirring dispersion time is greater than 20 min; and the heating stirring temperature is 80-100°C. The present application controls the volume of the Cu(NO3)2 solution, the mass of the Tween and the mass of the carbon nanotube powder to ensure that the carbon nanotube can be uniformly wrapped and a large amount of copper particles will not be accumulated, and controls the concentration of the Cu(NO3)2 solution to provide sufficient copper source for the reaction process.

[0018] The preparation method of the 4J50-CNTs / Cu composite wire for electronic packaging has the characteristics that the volume of the ammonia solution in step three and the mass of the carbon nanotube powder in step one are in the ratio of 1000-1100:1-1.6, wherein the unit of mass is g and the unit of volume is mL, the concentration of the ammonia solution is 0.12 g / mL-0.40 g / mL, the temperature of the constant-temperature stirring is 100 DEG C, and the time is more than 1 h. The copper nitrate in the reaction solution is completely reduced by controlling the volume of the ammonia solution and the mass of the carbon nanotube powder.

[0019] The preparation method of the 4J50-CNTs / Cu composite wire for electronic packaging has the characteristics that the volume ratio of H2 and Ar in the H2-Ar atmosphere in step five is 1:9, the temperature of the heating reduction is 550 DEG C, and the time is more than 2 h. The oxidized carbon nanotube / copper oxide powder is fully reduced by controlling the reduction parameters.

[0020] The preparation method of the 4J50-CNTs / Cu composite wire for electronic packaging has the characteristics that the discharge plasma sintering condition in step six is that the heating rate is 100 DEG C / min, the temperature is heated to 900 DEG C under the pressure of 45 MPa, and the temperature is kept for 10 min, and the inner diameter of the graphite mold is 30 mm. The carbon nanotube composite powder is sintered into a composite rod by controlling the discharge plasma sintering condition.

[0021] The preparation method of the 4J50-CNTs / Cu composite wire for electronic packaging has the characteristics that the process of the hot extrusion in step eight is that the forming piece is heated to 760 DEG C-780 DEG C and kept for more than 2 h, and then the hot extrusion is carried out with the extrusion ratio of 10:1 and the extrusion speed of 0.3 m / min-0.35 m / min. The composite interface bonding performance is strengthened by controlling the parameters of the hot extrusion.

[0022] The preparation method of the 4J50-CNTs / Cu composite wire for electronic packaging has the characteristics that the processing rate of each pass of the multi-pass drawing in step nine is 20%, and the vacuum annealing is carried out when the diameter of the extruded rod blank is 10 mm and 6 mm. The extruded rod blank is uniformly drawn by controlling the processing rate of each pass of the multi-pass drawing, and the interface element diffusion is promoted by the vacuum annealing, so that the air tightness of the composite wire is ensured.

[0023] Compared with the prior art, the present application has the following advantages:

[0024] 1. The application realizes that the nano-copper particles uniformly cover the surface of the carbon nanotubes through the surface modification process, reduces the wetting angle of the copper and the carbon nanotube interface in the hot-pressing sintering process, improves the binding property of the composite interface, and the copper layer acts as a spacer layer to effectively prevent the agglomeration of the carbon nanotubes.

[0025] 2. The application adopts the spark plasma sintering to prepare the composite block material with high density, and the subsequent drawing process under high temperature conditions and multiple annealing treatments promote the diffusion between Cu and Fe and Ni, accelerate the metallurgical bonding between the interfaces, and improve the interface bonding strength, so that the prepared composite wire has excellent air tightness.

[0026] 3. The application adds the carbon nanotubes into the copper matrix through the surface modification process, improves the conductivity and thermal conductivity of the copper matrix, reduces the expansion coefficient of the copper matrix, reduces the expansion or shrinkage difference between the glass and the metal in the connecting process, and ensures the sealing quality.

[0027] 4. The prepared composite wire has high strength and high conductivity and thermal conductivity of CNTs without sacrificing the original low expansion coefficient, greatly improves the mechanical properties and conductivity and thermal conductivity of the 4J50 / Cu composite wire, improves the bonding strength of the 4J50 / Cu composite interface through high-temperature long-time heat treatment, effectively ensures the air tightness of the composite wire, widens the application field of the 4J50 / Cu composite wire, breaks the bottleneck that the performance of the 4J50 / Cu material cannot be further improved, and provides a new idea for further improving the performance of the 4J50 / Cu material.

[0028] 5. The application prepares the CNTs / Cu composite powder with uniformly dispersed CNTs by surface modification of the CNTs, then prepares the high-density CNTs / Cu composite block body by spark plasma sintering, and finally prepares the CNTs / Cu composite wire by combining the layer coating preparation technology and the extrusion drawing process, which significantly improves the strength and conductivity and thermal conductivity of the material without sacrificing the original air tightness and low expansion coefficient, and with the further development of the electronic packaging field, the new carbon nanotube reinforced 4J50 / Cu composite wire applied in the high-performance electronic component field will become an inevitable trend.

[0029] The technical solutions of the application will be further described in detail below with reference to the drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 is the SEM diagram of the surface modified carbon nanotube composite powder prepared in Example 1 of the application.

[0031] Figure 2Raman spectrum of the surface-modified carbon nanotube composite powder prepared in Example 1 of the present application.

[0032] Figure 3 Structure diagram of the 4J50-CNTs / Cu composite wire prepared in Example 1 of the present application. DETAILED DESCRIPTION

[0033] Example 1

[0034] This example comprises the following steps:

[0035] Step one, 1g of CNTs is weighed, and then the weighed CNTs powder is dissolved in 200ml of deionized water, and ultrasonic dispersion is carried out under the condition of ultrasonic oscillation for 20min to obtain a precursor solution;

[0036] Step two, 1000ml of Cu(NO3)2 solution with a concentration of 0.12g / mL and 0.5g of Tween are sequentially added into the precursor solution obtained in step one, and stirring and dispersion are carried out for 20min, then magnetic stirring is started to heat, until the temperature rises to 80℃, to obtain a mixed precursor solution;

[0037] Step three, 1000ml of ammonia solution with a concentration of 0.12g / mL is slowly added dropwise into the mixed precursor solution, and after the dropwise addition is completed, constant temperature stirring is carried out at 100℃ for 1h to obtain a reaction solution;

[0038] Step four, after the reaction solution obtained in step three is fully reacted, the reaction solution is filtered, and deionized water is used for multiple times of cleaning to remove impurities, and the filtered product is freeze-dried to obtain carbon nanotube oxide / copper oxide powder (CNTs / CuO);

[0039] Step five, the carbon nanotube oxide / copper oxide powder obtained in step four is reduced at 550℃ for 2h in a 10% H2-90% Ar atmosphere to obtain surface-modified carbon nanotube composite powder (CNTs / Cu);

[0040] Step six, the surface-modified carbon nanotube composite powder obtained in step five is loaded into a graphite mold with an inner diameter of 30mm, and is sintered by spark plasma sintering (SPS) at a pressure of 45MPa and a heating rate of 100℃ / min at 900℃ for 10min, and a CNTs / Cu composite rod is obtained by sintering;

[0041] Step seven, the CNTs / Cu composite rod obtained in step six is acid pickled and dried with a 4J50 sheath, the dried CNTs / Cu composite rod is loaded into the 4J50 sheath, and is placed under a hydraulic press for hydraulic expansion to remove interfacial gas, and a 4J50-CNTs / Cu composite ingot is obtained;

[0042] Step 8: The 4J50-CNTs / Cu composite ingot obtained in Step 7 is cold isostatically pressed to obtain a 4J50-CNTs / Cu molded part. Then, after holding at a temperature of 760℃~780℃ for 2 hours, it is hot extruded to obtain a 4J50-CNTs / Cu extruded bar blank with a diameter of 20mm.

[0043] Step Nine: Perform multi-pass drawing on the 4J50-CNTs / Cu extruded billets obtained in Step Eight, and perform high-vacuum annealing at diameters of 10mm and 6mm respectively. The diameters of the extruded billets after each pass are as follows: Ф18mm, Ф16mm, Ф15mm, Ф14mm, Ф13mm, Ф12mm, Ф12.5mm, Ф12.0mm, Ф11.5mm, Ф11.0mm, Ф10.5mm, Ф10.0mm, Ф9.5mm, Ф9.0mm, Ф8.6mm, Ф8.2mm, Ф7.8mm, Ф7. Highly concentric 4J50-CNTs / Cu composite wires were obtained by using the following diameters: 0.4mm, 7.0mm, 6.6mm, 6.2mm, 5.8mm, 5.4mm, 5.0mm, 4.8mm, 4.2mm, 4.0mm, 3.80mm, 3.65mm, 3.55mm, 3.40mm, 3.20mm, 3.13mm, 2.95mm, 2.80mm, 2.75mm, 2.68mm, 2.40mm, 2.20mm, and 2.00mm. (See...) Figure 3 .

[0044] Testing revealed that the surface-modified carbon nanotube-reinforced 4J50 / Cu composite wire prepared in this embodiment has a strength of 724 MPa, which is 6% higher than that of wires of the same size prepared by traditional methods. The wire also exhibits an electrical conductivity of 49% IACS, a 19% reduction in resistivity compared to wires of the same size prepared by traditional methods, and a leakage rate of no more than 1×10⁻⁶. -10 Pa·m 3 / s, concentricity less than 0.05mm.

[0045] Figure 1 These are SEM images of the surface-modified carbon nanotube composite powder prepared in this embodiment. Figure 1 As can be seen, the copper nanoparticles in the surface-modified carbon nanotube composite powder completely encapsulate the carbon nanotubes, effectively preventing the carbon nanotubes from agglomerating.

[0046] Figure 2 This is the Raman spectrum of the surface-modified carbon nanotube composite powder prepared in this embodiment, from... Figure 2 It can be seen from this that Figure 2 The presence of D and G peaks characteristic of carbon materials indicates that carbon nanotubes exist within the matrix, as shown in Figure I.D / I G = 0.37 The value is small, indicating that the carbon nanotubes are well dispersed.

[0047] Figure 3 is a structural schematic diagram of the 4J50-CNTs / Cu composite wire prepared in this embodiment, from which Figure 3 It can be seen from the figure that the 4J50 in the 4J50-CNTs / Cu composite wire prepared in this embodiment wraps the CNTs outside the Cu.

[0048] Example 2

[0049] This embodiment includes the following steps:

[0050] Step one, weigh 1.2g of CNTs, then dissolve the weighed CNTs powder in 200ml of deionized water, and ultrasonically disperse under the condition of ultrasonic oscillation for 20min to obtain a precursor solution;

[0051] Step two, weigh 1000ml of Cu(NO3)2 solution with a concentration of 0.24g / mL, and 0.6g of Tween into the precursor solution obtained in step one, stir and disperse for 20min, then start heating under magnetic stirring until the temperature rises to 90℃, to obtain a mixed precursor solution;

[0052] Step three, weigh 1000ml of ammonia solution with a concentration of 0.24g / mL, and slowly drop it into the mixed precursor solution, after the drop is completed, stir at 100℃ for 1h to obtain a reaction solution;

[0053] Step four, after the reaction solution obtained in step three is fully reacted, the reaction solution is filtered, washed with deionized water several times to remove impurities, and the filtered product is freeze-dried to obtain carbon nanotube / copper oxide powder (CNTs / CuO);

[0054] Step five, reduce the carbon nanotube / copper oxide powder obtained in step four in a 10% H2-90% Ar atmosphere at 550℃ for 2h to obtain a surface-modified carbon nanotube composite powder (CNTs / Cu);

[0055] Step six, load the surface-modified carbon nanotube composite powder obtained in step five into a graphite mold with an inner diameter of 30mm, and sinter at 900℃ for 10min under a pressure of 45MPa at a heating rate of 100℃ / min by spark plasma sintering (SPS) to obtain a CNTs / Cu composite rod;

[0056] Step seven, the CNTs / Cu composite rod obtained in step six is sleeved with 4J50 and pickled and dried, the dried CNTs / Cu composite rod is loaded into 4J50, and then placed under a hydraulic machine for hydraulic expansion to remove interface gas, and a 4J50-CNTs / Cu composite ingot is obtained;

[0057] Step eight, the 4J50-CNTs / Cu composite ingot obtained in step seven is cold isostatic pressed to obtain a 4J50-CNTs / Cu formed piece, and then heat extruded after being kept at a temperature of 760-780℃ for 2h to obtain a 4J50-CNTs / Cu extruded rod blank with a diameter of 20mm;

[0058] Step nine, the 4J50-CNTs / Cu extruded rod blank obtained in step eight is subjected to multi-pass drawing, and high vacuum annealing is performed when the diameter is 10mm and 6mm, respectively. The diameter of the extruded rod blank after each pass is: 18mm, 16mm, 15mm, 14mm, 13mm, 12mm, 12.5mm, 12.0mm, 11.5mm, 11.0mm, 10.5mm, 10.0mm, 9.5mm, 9.0mm, 8.6mm, 8.2mm, 7.8mm, 7.4mm, 7.0mm, 6.6mm, 6.2mm, 5.8mm, 5.4mm, 5.0mm, 4.8mm, 4.2mm, 4.0mm, 3.80mm, 3.65mm, 3.55mm, 3.40mm, 3.20mm, 3.13mm, 2.95mm, 2.80mm, 2.75mm, 2.68mm, 2.40mm, 2.20mm, 2.00mm, to obtain a 4J50-CNTs / Cu composite wire with high concentricity.

[0059] It is detected that the surface modified carbon nanotube reinforced 4J50 / Cu composite wire prepared in the embodiment has a strength of 739MPa, which is increased by 8% compared with the strength of the same size wire prepared by a traditional method, the wire has an electrical conductivity of 52%IACS, which is reduced by 22% compared with the electrical resistivity of the same size wire prepared by the traditional method, the air leakage rate is not more than 1×10 -10 Pa·m 3 / s, and the concentricity is less than 0.05mm.

[0060] Example 3

[0061] The embodiment includes the following steps:

[0062] Step one, 1.4g of CNTs is weighed, and then the weighed CNTs powder is dissolved in 200ml of deionized water, and ultrasonic dispersion is carried out under the condition of ultrasonic oscillation for 20min to obtain a precursor solution;

[0063] Step two, 1000ml of Cu(NO3)2 solution with a concentration of 0.36g / mL and 0.7g of Tween are sequentially added into the precursor solution obtained in step one, and stirring and dispersion are carried out for 20min, then magnetic stirring is started to heat, until the temperature rises to 100℃, to obtain a mixed precursor solution;

[0064] Step three, 1000ml of ammonia solution with a concentration of 0.36g / mL is slowly added dropwise into the mixed precursor solution, and after the dropwise addition is completed, constant temperature stirring is carried out at 100℃ for 1h to obtain a reaction solution;

[0065] Step four, after the reaction solution obtained in step three is fully reacted, the reaction solution is filtered, and deionized water is used for multiple washing to remove impurities, and the filtered product is freeze-dried to obtain carbon nanotube / copper oxide powder (CNTs / CuO);

[0066] Step five, the carbon nanotube / copper oxide powder obtained in step four is reduced at 550℃ for 2h in a 10% H2-90% Ar atmosphere to obtain surface-modified carbon nanotube composite powder (CNTs / Cu);

[0067] Step six, the surface-modified carbon nanotube composite powder obtained in step five is loaded into a graphite mold with an inner diameter of 30mm, and is sintered by spark plasma sintering (SPS) at a pressure of 45MPa and a heating rate of 100℃ / min at 900℃ for 10min, and a CNTs / Cu composite rod is obtained by sintering;

[0068] Step seven, the CNTs / Cu composite rod obtained in step six is acid pickled and dried with a 4J50 package, the dried CNTs / Cu composite rod is loaded into a 4J50 package, and is placed under a hydraulic press for hydraulic expansion to remove interfacial gas, and a 4J50-CNTs / Cu composite ingot is obtained;

[0069] Step eight, the 4J50-CNTs / Cu composite ingot obtained in step seven is cold isostatic pressed to obtain a 4J50-CNTs / Cu formed piece, and then hot extrusion processing is carried out at a temperature of 760℃-780℃ for 2h to obtain a 4J50-CNTs / Cu extruded rod blank with a diameter of 20mm;

[0070] Step nine, the 4J50-CNTs / Cu extruded rod obtained in step eight is subjected to multi-pass drawing, and high vacuum annealing is performed when the diameter is 10 mm and 6 mm, respectively, and the diameter of the extruded rod after each pass is: 18 mm, 16 mm, 15 mm, 14 mm, 13 mm, 12 mm, 12.5 mm, 12.0 mm, 11.5 mm, 11.0 mm, 10.5 mm, 10.0 mm, 9.5 mm, 9.0 mm, 8.6 mm, 8.2 mm, 7.8 mm, 7.4 mm, 7.0 mm, 6.6 mm, 6.2 mm, 5.8 mm, 5.4 mm, 5.0 mm, 4.8 mm, 4.2 mm, 4.0 mm, 3.80 mm, 3.65 mm, 3.55 mm, 3.40 mm, 3.20 mm, 3.13 mm, 2.95 mm, 2.80 mm, 2.75 mm, 2.68 mm, 2.40 mm, 2.20 mm, 2.00 mm, to obtain a 4J50-CNTs / Cu composite wire with high concentricity.

[0071] It is detected that the surface modified carbon nanotube reinforced 4J50 / Cu composite wire prepared in the embodiment has a strength of 744 MPa, which is increased by 9% compared with the strength of the same size wire prepared by the traditional method, the wire has an electrical conductivity of 53% IACS, which is reduced by 23% compared with the electrical resistivity of the same size wire prepared by the traditional method, the air leakage rate is not more than 1x10 -10 Pa·m 3 / s, and the concentricity is less than 0.05 mm.

[0072] Example 4

[0073] The embodiment includes the following steps:

[0074] Step one, 1.6 g of CNTs is weighed, and then the weighed CNTs powder is dissolved in 200 ml of deionized water, and ultrasonic dispersion is performed under ultrasonic vibration for 20 min to obtain a precursor solution;

[0075] Step two, 1050 ml of Cu(NO3)2 solution with a concentration of 0.40 g / mL and 0.8 g of Tween are sequentially added to the precursor solution obtained in step one, and stirring and dispersion are performed for 20 min, then magnetic stirring is started to heat, and the temperature is raised to 100°C to obtain a mixed precursor solution;

[0076] Step three, 1050 ml of ammonia solution with a concentration of 0.40 g / mL is slowly added dropwise into the mixed precursor solution, and after the dropwise addition is completed, constant temperature stirring is performed at 100°C for 1 h to obtain a reaction solution;

[0077] Step four, after the reaction liquid obtained in step three is fully reacted, the reaction liquid is filtered, washed with deionized water for multiple times to remove impurities, and the filtered product is freeze-dried to obtain carbon nanotube oxide / copper oxide powder (CNTs / CuO);

[0078] Step five, the carbon nanotube oxide / copper oxide powder obtained in step four is reduced at 550°C for 2h in a 10% H2-90% Ar atmosphere to obtain surface-modified carbon nanotube composite powder (CNTs / Cu);

[0079] Step six, the surface-modified carbon nanotube composite powder obtained in step five is loaded into a graphite mold with an inner diameter of 30mm, and sintered at 900°C for 10min by spark plasma sintering (SPS) at a pressure of 45MPa and a heating rate of 100°C / min, to obtain a CNTs / Cu composite rod by sintering;

[0080] Step seven, the CNTs / Cu composite rod obtained in step six is pickled and dried with a 4J50 package, the dried CNTs / Cu composite rod is loaded into a 4J50 package, and then placed under a hydraulic press for hydraulic expansion to remove interfacial gas, to obtain a 4J50-CNTs / Cu composite ingot;

[0081] Step eight, the 4J50-CNTs / Cu composite ingot obtained in step seven is cold isostatic pressed to obtain a 4J50-CNTs / Cu formed piece, which is then heat treated at a temperature of 760°C-780°C for 2h and then subjected to hot extrusion processing to obtain a 4J50-CNTs / Cu extruded rod blank with a diameter of 20mm;

[0082] Step nine, the 4J50-CNTs / Cu extruded rod blank obtained in step eight is subjected to multi-pass drawing, and high vacuum annealing is performed when the diameter is 10mm and 6mm, respectively. The diameter of the extruded rod blank after each pass is: Ф18mm, Ф16mm, Ф15mm, Ф14mm, Ф13mm, Ф12mm, Ф12.5mm, Ф12.0mm, Ф11.5mm, Ф11.0mm, Ф10.5mm, Ф10.0mm, Ф9.5mm, Ф9.0mm, Ф8.6mm, Ф8.2mm, Ф7.8mm, Ф7.4mm, Ф7.0mm, Ф6.6mm, Ф6.2mm, Ф5.8mm, Ф5.4mm, Ф5.0mm, Ф4.8mm, Ф4.2mm, Ф4.0mm, Ф3.80mm, Ф3.65mm, Ф3.55mm, Ф3.40mm, Ф3.20mm, Ф3.13mm, Ф2.95mm, Ф2.80mm, Ф2.75mm, Ф2.68mm, Ф2.40mm, Ф2.20mm, Ф2.00mm, to obtain a 4J50-CNTs / Cu composite wire with high concentricity.

[0083] The surface modified carbon nanotube reinforced 4J50 / Cu composite wire prepared in the embodiment is detected to have a strength of 759 MPa, which is increased by 11% compared with the strength of the same size wire prepared by the traditional method, the wire has an electrical conductivity of 53% IACS, which is reduced by 23% compared with the electrical resistivity of the same size wire prepared by the traditional method, the air leakage rate is not more than 1x10 -10 Pa·m 3 / s, and the concentricity is less than 0.05 mm.

[0084] Embodiment 5

[0085] The embodiment includes the following steps:

[0086] Step one, 1.6g of CNTs is weighed, and then the weighed CNTs powder is dissolved in 200ml of deionized water, and ultrasonic dispersion is performed under the condition of ultrasonic oscillation for 20min to obtain a precursor solution;

[0087] Step two, 1100ml of Cu(NO3)2 solution with a concentration of 0.40g / mL and 1g of Tween are sequentially added into the precursor solution obtained in step one, and stirring and dispersion are performed for 20min, then magnetic stirring is started to heat, until the temperature is increased to 100℃, to obtain a mixed precursor solution;

[0088] Step three, 1100ml of ammonia solution with a concentration of 0.40g / mL is slowly added dropwise into the mixed precursor solution, and after the dropwise addition is completed, constant temperature stirring is performed at 100℃ for 1h to obtain a reaction solution;

[0089] Step four, after the reaction solution obtained in step three is fully reacted, the reaction solution is filtered, and deionized water is used for multiple times of cleaning to remove impurities, and the filtered product is freeze-dried to obtain carbon nanotube / oxidized copper powder (CNTs / CuO);

[0090] Step five, the carbon nanotube / oxidized copper powder obtained in step four is reduced at 550℃ for 2h in a 10% H2-90% Ar atmosphere to obtain surface modified carbon nanotube composite powder (CNTs / Cu);

[0091] Step six, the surface modified carbon nanotube composite powder obtained in step five is loaded into a graphite mold with an inner diameter of 30mm, and is sintered by spark plasma sintering (SPS) at a pressure of 45MPa at a heating rate of 100℃ / min at 900℃ for 10min, to obtain a CNTs / Cu composite rod by sintering;

[0092] Step seven, the CNTs / Cu composite rod obtained in step six is sleeved with 4J50 and pickled and dried, the dried CNTs / Cu composite rod is loaded into 4J50, and then is placed under a hydraulic machine to be expanded by hydraulic pressure to remove interface gas, and a 4J50-CNTs / Cu composite ingot is obtained;

[0093] Step eight, the 4J50-CNTs / Cu composite ingot obtained in step seven is cold isostatic pressed to obtain a 4J50-CNTs / Cu formed piece, and then is heat extruded after being kept at a temperature of 760-780℃ for 2h to obtain a 4J50-CNTs / Cu extruded rod blank with a diameter of 20mm;

[0094] Step nine, the 4J50-CNTs / Cu extruded rod blank obtained in step eight is drawn in multiple passes, and high vacuum annealing is performed when the diameter is 10mm and 6mm, respectively, and the diameter of the extruded rod blank after each pass is: 18mm, 16mm, 15mm, 14mm, 13mm, 12mm, 12.5mm, 12.0mm, 11.5mm, 11.0mm, 10.5mm, 10.0mm, 9.5mm, 9.0mm, 8.6mm, 8.2mm, 7.8mm, 7.4mm, 7.0mm, 6.6mm, 6.2mm, 5.8mm, 5.4mm, 5.0mm, 4.8mm, 4.2mm, 4.0mm, 3.80mm, 3.65mm, 3.55mm, 3.40mm, 3.20mm, 3.13mm, 2.95mm, 2.80mm, 2.75mm, 2.68mm, 2.40mm, 2.20mm, 2.00mm, and a 4J50-CNTs / Cu composite wire with high concentricity is obtained.

[0095] It is detected that the surface modified carbon nanotube reinforced 4J50 / Cu composite wire prepared in the embodiment has a strength of 746MPa, which is increased by 9% compared with the strength of the same size wire prepared by a traditional method, the wire has an electrical conductivity of 52%IACS, which is reduced by 22% compared with the electrical resistivity of the same size wire prepared by the traditional method, the air leakage rate is not more than 1×10 -10 Pa·m 3 / s, and the concentricity is less than 0.05mm.

[0096] The above is only a preferred embodiment of the present application, and does not limit the present application. Any simple modification, change and equivalent change made according to the technical essence of the present application to the above embodiment are still within the protection scope of the technical solution of the present application.

Claims

1. A method for preparing a 4J50-CNTs / Cu composite wire for electronic packaging, characterized by, The method comprises the following steps: Step one, carbon nanotube powder is added into deionized water, and then ultrasonic dispersion is carried out to obtain a precursor solution; Step two, Cu(NO3)2 solution and Tween are sequentially added into the precursor solution obtained in step one, and then stirring and dispersion are carried out, and then heating and stirring are carried out to obtain a mixed precursor solution; Step three, under the condition of heating and stirring, ammonia solution is slowly added dropwise into the mixed precursor solution obtained in step two, and then constant temperature stirring is carried out to obtain a reaction solution; Step four, the reaction solution obtained in step three is filtered, and then the filtered product is washed with deionized water for multiple times and then freeze-dried to obtain oxidized carbon nanotube / copper oxide powder; Step five, the oxidized carbon nanotube / copper oxide powder obtained in step four is heated and reduced in H2-Ar atmosphere to obtain surface-modified carbon nanotube composite powder; Step six, the surface-modified carbon nanotube composite powder obtained in step five is loaded into a graphite mold, and then spark plasma sintering is carried out to obtain a composite rod; Step seven, the composite rod obtained in step six and 4J50 sheath are subjected to pickling and drying, and then the dried composite rod is loaded into the dried 4J50 sheath, and then is placed under a hydraulic press to carry out hydraulic pressure expansion to obtain a composite ingot; Step eight, the composite ingot obtained in step seven is subjected to cold isostatic pressing to obtain a formed piece, and then hot extrusion is carried out to obtain an extruded rod blank; Step nine, the extruded rod blank obtained in step eight is subjected to multi-pass drawing to obtain a 4J50-CNTs / Cu composite wire.

2. The method for preparing a 4J50-CNTs / Cu composite wire for electronic packaging according to claim 1, characterized in that, In step one, the mass of the carbon nanotube powder and the volume of the deionized water are in the ratio of 1-1.6:200, wherein the unit of mass is g and the unit of volume is mL; the ultrasonic dispersion time is greater than 20 min.

3. The method for preparing a 4J50-CNTs / Cu composite wire for electronic packaging according to claim 1, characterized in that, In step two, the volume of the Cu(NO3)2 solution, the mass of the Tween and the mass of the carbon nanotube powder in step one are in the ratio of 1000-1100:0.5-1:1-1.6, wherein the unit of mass is g and the unit of volume is mL; the concentration of the Cu(NO3)2 solution is 0.12-0.40 g / mL; the stirring and dispersion time is greater than 20 min; and the heating and stirring temperature is 80-100°C.

4. The method for preparing a 4J50-CNTs / Cu composite wire for electronic packaging according to claim 1, characterized in that, In step three, the volume of the ammonia solution and the mass of the carbon nanotube powder in step one are in the ratio of 1000-1100:1-1.6, wherein the unit of mass is g and the unit of volume is mL; the concentration of the ammonia solution is 0.12-0.40 g / mL; the constant temperature stirring temperature is 100°C; and the time is greater than 1 h.

5. The method for preparing a 4J50-CNTs / Cu composite wire for electronic packaging according to claim 1, characterized in that, In step five, the volume ratio of H2 to Ar in the H2-Ar atmosphere is 1:9; the heating and reduction temperature is 550°C; and the time is greater than 2 h.

6. The method for preparing a 4J50-CNTs / Cu composite wire for electronic packaging according to claim 1, characterized in that, In step six, the spark plasma sintering condition is that the graphite mold is heated to 900°C at a heating rate of 100°C / min under a pressure of 45 MPa and then is kept for 10 min; and the inner diameter of the graphite mold is 30 mm.

7. The method for preparing a 4J50-CNTs / Cu composite wire for electronic packaging according to claim 1, characterized in that, The hot extrusion process in step eight is as follows: the shaped piece is heated to 760-780℃ and kept for 2 hours or more, and then hot extrusion is carried out at an extrusion ratio of 10:1 and an extrusion speed of 0.3-0.35 m / min.

8. The method for preparing a 4J50-CNTs / Cu composite wire for electronic packaging according to claim 1, characterized in that, The processing rate of each pass in the multi-pass drawing in step nine is 20%, and vacuum annealing is carried out when the diameter of the extruded rod blank is 10 mm and 6 mm.

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