A cutting blade for packaging materials and its preparation method

Abstract

This invention discloses a cutting blade made of encapsulated material, comprising, by weight, 40-60 parts abrasive, 10-15 parts silver powder, 12-18 parts ultrafine copper powder, 2-7 parts conductive whiskers, 1-5 parts carbon nanotubes, 20-30 parts resin powder, and 0.5-3 parts dispersant. This invention utilizes the synergistic effect of ultrafine copper powder and dispersant to prevent silver powder agglomeration, thus avoiding impacts on cutting quality and blade lifespan. Furthermore, the synergistic effect of ultrafine copper powder dispersed in the material and carbon nanotubes enhances the structural strength of the cutting blade.

Description

Technical Field

[0001] This invention relates to the field of QFN cutting blade technology, and in particular to a cutting blade for packaging materials and its preparation method. Background Technology

[0002] QFN packaging is popular in the chip market due to its advantages such as small size, light weight, good heat dissipation, good electrical performance, and high reliability. During packaging, the QFN material needs to be processed and cut to match the chip.

[0003] In the prior art, patent application number 202211720557.3 discloses a conductive resin-based QFN cutting blade and its preparation method. This method uses a dispersant to enhance the uniformity of silver powder distribution in the powder, resulting in a more uniform distribution of fillers and other components in the blade body. This leads to more uniform and higher-quality cut products, thus mitigating the tailing effect when cutting QFN materials. However, the introduction of a dispersant, while addressing agglomeration, may affect the strength and structure of the cutting blade, thereby impacting its durability and lifespan. Summary of the Invention

[0004] The purpose of this invention is to provide a packaging material cutting blade and its preparation method. The synergistic effect of ultrafine copper powder and dispersant can avoid the agglomeration of silver powder, thus avoiding affecting the cutting quality and the service life of the cutting blade. Furthermore, the synergistic effect of carbon nanotubes in the ultrafine copper powder dispersed in the material improves the structural strength of the cutting blade.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: a packaging material cutting blade, comprising the following components by weight: 40-60 parts abrasive, 10-15 parts silver powder, 12-18 parts ultrafine copper powder, 2-7 parts conductive whiskers, 1-5 parts carbon nanotubes, 20-30 parts resin powder, and 0.5-3 parts dispersant.

[0006] As a further optimization, the abrasive is diamond, silicon carbide, or cubic boron nitride.

[0007] As a further optimization, the particle size of the ultrafine copper powder is 0.2-2 μm.

[0008] As a further optimization, the conductive whiskers are graphite whiskers with a length of 50-100 μm.

[0009] As a further optimization, the aspect ratio of the carbon nanotubes is (5000-15000):1. Carbon nanotubes have better strength at a larger aspect ratio and can enhance conductivity. The carbon nanotubes are dispersed in the material and have a longer length than conventional particles, thus forming a core and structural support points to improve the strength of the cutting blade.

[0010] As a further optimization, the resin powder is phenolic resin powder or epoxy resin powder.

[0011] As a further optimization, the dispersant is a nano-rare earth or nano-ceramic.

[0012] This invention also provides a method for preparing a cutting blade for packaging materials, which includes the following steps:

[0013] S1) Accurately weigh each material;

[0014] S2) Silver powder and ultrafine copper powder are added to a mixing tank in sequence and mixed. Dispersant is added and mixed evenly. Conductive whiskers and carbon nanotubes are added and mixed evenly. Finally, abrasive and resin powder are added and mixed evenly to obtain a mixture.

[0015] S3) The mixture is sieved, fed into the press, and pressed under pressure to obtain a cold-pressed blank;

[0016] S4) Sintering: The cold-pressed billet is placed in a sintering furnace for sintering. After sintering is completed, it is cooled and removed, and the burrs are removed to obtain the primary billet.

[0017] S5) The outer circle is cut by slow wire cutting and the inner hole is machined. The burrs are removed to obtain the blank.

[0018] S6) The blank is placed in a double-end thinning machine for processing to obtain a packaging material cutting blade.

[0019] As a further optimization, the pressure in S3 is 2-5 t / cm. 2 Hold pressure for 5-10 seconds.

[0020] As a further optimization, the heating rate in S4 is 50-55℃ / min, the sintering temperature is 450-600℃, and the holding time is 10-20min.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The cutting blade contains ultrafine copper powder, which can reduce friction between components during the material mixing stage and play a lubricating and dispersing role in the mixing of components. In synergy with the dispersant, it can prevent the silver powder from agglomerating, thus avoiding affecting the cutting quality and the service life of the cutting blade.

[0023] 2. Ultrafine copper powder itself has good electrical conductivity, high hardness, and high compressive strength. It works synergistically with carbon nanotubes dispersed in the material to improve the structural strength of the cutting blade.

[0024] 3. The dispersant is selected from nano-rare earth or nano-ceramics. The nano-sized particles inhibit the growth of silver powder or ultrafine copper powder grains, which is more suitable for solving the agglomeration of metal particles. Detailed Implementation

[0025] The following are specific embodiments of the present invention, which further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0026] Example 1

[0027] A cutting blade for packaging materials comprises the following components by weight: 51 parts diamond, 13 parts silver powder, 17 parts ultrafine copper powder, 5 parts graphite whiskers, 5 parts carbon nanotubes, 26 parts phenolic resin powder, and 2 parts nano-rare earth.

[0028] The preparation method is as follows: S1) Accurately weigh each material; S2) Add silver powder and ultrafine copper powder to a mixing tank in sequence and mix, add nano-rare earth and mix evenly, then add graphite whiskers and carbon nanotubes and mix evenly, and finally add diamond and phenolic resin powder and mix evenly to obtain a mixture; S3) Sieve the mixture, feed it into a press, and press it at a pressure of 5t / cm. 2 S4) Sintering: The cold-pressed blank is placed in a sintering furnace for sintering. The heating rate is 50℃ / min, the sintering temperature is 550℃, and the holding time is 10min. After sintering, it is cooled and removed to remove burrs and obtain a primary blank. S5) The outer circle is cut by slow wire cutting and the inner hole is machined. The burrs are removed to obtain a blank. S6) The blank is placed in a double-end face thinning machine for processing to obtain a packaging material cutting blade.

[0029] Example 2

[0030] A cutting blade for packaging materials comprises the following components by weight: 45 parts diamond, 15 parts silver powder, 12 parts ultrafine copper powder, 6 parts graphite whiskers, 3 parts carbon nanotubes, 24 parts epoxy resin powder, and 3 parts nano-rare earth.

[0031] The preparation method is as follows: S1) Accurately weigh each material; S2) Add silver powder and ultrafine copper powder to a mixing tank in sequence and mix, add nano-rare earth and mix evenly, then add graphite whiskers and carbon nanotubes and mix evenly, and finally add diamond and epoxy resin powder and mix evenly to obtain a mixture; S3) Sieve the mixture, feed it into a press, and press it at a pressure of 5t / cm. 2 S4) Sintering: The cold-pressed blank is placed in a sintering furnace for sintering. The heating rate is 50℃ / min, the sintering temperature is 550℃, and the holding time is 10min. After sintering, it is cooled and removed to remove burrs and obtain a primary blank. S5) The outer circle is cut by slow wire cutting and the inner hole is machined. The burrs are removed to obtain a blank. S6) The blank is placed in a double-end face thinning machine for processing to obtain a packaging material cutting blade.

[0032] Example 3

[0033] A cutting blade for packaging materials comprises the following components by weight: 57 parts cubic boron nitride, 11 parts silver powder, 12 parts ultrafine copper powder, 3 parts graphite whiskers, 5 parts carbon nanotubes, 26 parts phenolic resin powder, and 3 parts nano-ceramics.

[0034] The preparation method is as follows: S1) Accurately weigh each material; S2) Add silver powder and ultrafine copper powder to a mixing tank in sequence and mix, then add nano-ceramics and mix evenly, then add graphite whiskers and carbon nanotubes and mix evenly, and finally add cubic boron nitride and phenolic resin powder and mix evenly to obtain a mixture; S3) Sieve the mixture, feed it into a press, and press it at a pressure of 5t / cm. 2 S4) Sintering: The cold-pressed blank is placed in a sintering furnace for sintering. The heating rate is 50℃ / min, the sintering temperature is 550℃, and the holding time is 10min. After sintering, it is cooled and removed to remove burrs and obtain a primary blank. S5) The outer circle is cut by slow wire cutting and the inner hole is machined. The burrs are removed to obtain a blank. S6) The blank is placed in a double-end face thinning machine for processing to obtain a packaging material cutting blade.

[0035] Example 4

[0036] A cutting blade for packaging materials comprises the following components by weight: 52 parts cubic boron nitride, 12 parts silver powder, 15 parts ultrafine copper powder, 4 parts graphite whiskers, 3 parts carbon nanotubes, 25 parts epoxy resin powder, and 1 part nano-ceramics.

[0037] The preparation method is as follows: S1) Accurately weigh each material; S2) Add silver powder and ultrafine copper powder to a mixing tank in sequence and mix, add nano-ceramics and mix evenly, then add graphite whiskers and carbon nanotubes and mix evenly, finally add cubic boron nitride and epoxy resin powder and mix evenly to obtain a mixture; S3) Sieve the mixture, feed it and press it at a pressure of 5t / cm. 2 S4) Sintering: The cold-pressed blank is placed in a sintering furnace for sintering. The heating rate is 50℃ / min, the sintering temperature is 550℃, and the holding time is 10min. After sintering, it is cooled and removed to remove burrs and obtain a primary blank. S5) The outer circle is cut by slow wire cutting and the inner hole is machined. The burrs are removed to obtain a blank. S6) The blank is placed in a double-end face thinning machine for processing to obtain a packaging material cutting blade.

[0038] Example 5

[0039] A cutting blade for packaging materials comprises the following components by weight: 41 parts diamond, 15 parts silver powder, 18 parts ultrafine copper powder, 5 parts graphite whiskers, 2 parts carbon nanotubes, 26 parts phenolic resin powder, and 2 parts nano-rare earth.

[0040] The preparation method is as follows: S1) Accurately weigh each material; S2) Add silver powder and ultrafine copper powder to a mixing tank in sequence and mix, add nano-rare earth and mix evenly, then add graphite whiskers and carbon nanotubes and mix evenly, finally add diamond and phenolic resin powder and mix evenly to obtain a mixture; S3) Sieve the mixture, feed it into a press, and press it at a pressure of 5t / cm. 2 S4) Sintering: The cold-pressed blank is placed in a sintering furnace for sintering. The heating rate is 50℃ / min, the sintering temperature is 550℃, and the holding time is 10min. After sintering, it is cooled and removed to remove burrs and obtain a primary blank. S5) The outer circle is cut by slow wire cutting and the inner hole is machined. The burrs are removed to obtain a blank. S6) The blank is placed in a double-end face thinning machine for processing to obtain a packaging material cutting blade.

[0041] Comparative Example 1

[0042] Compared to Example 1, no ultrafine copper powder was added in this application. The remaining components are in the following weight proportions: 60 parts diamond, 15 parts silver powder, 7 parts graphite whiskers, 5 parts carbon nanotubes, 30 parts phenolic resin powder, and 2 parts nano rare earth.

[0043] Comparative Example 2

[0044] Compared to Example 1, no nano-rare earth was added in this application. The remaining components are in the following weight proportions: 51 parts diamond, 13 parts silver powder, 19 parts ultrafine copper powder, 5 parts graphite whiskers, 5 parts carbon nanotubes, and 26 parts phenolic resin powder. In other words, the proportion of nano-rare earth was added to the ultrafine copper powder.

[0045] Comparative Example 3

[0046] Compared to Example 1, this application does not include ultrafine copper powder and nano rare earth. The remaining components are in the following weight proportions: 62 parts diamond, 15 parts silver powder, 7 parts graphite whiskers, 5 parts carbon nanotubes, and 30 parts phenolic resin powder.

[0047] Comparative Example 4

[0048] Ordinary blade.

[0049] Application Examples

[0050] The cutting blades prepared in Examples 1 to 5 and Comparative Examples 1 to 3 were used to cut QFN material. The cutting conditions were: rotation speed 30 krpm and cutting speed 50 mm / s. The experimental data are shown in the table below.

[0051] Wear rate (μm / m) Trail (μm) Burrs (μm) Example 1 0.72 87 22 Example 2 0.76 91 21 Example 3 0.74 88 23 Example 4 0.78 95 23 Example 5 0.76 96 25 Comparative Example 1 0.83 113 33 Comparative Example 2 0.86 117 34 Comparative Example 3 0.92 121 36 Comparative Example 4 0.97 135 38

[0052] The experimental data above show that adding ultrafine copper powder and dispersant to the cutting blade significantly improves the blade's wear rate, trailing phenomenon, and burrs. Ultrafine copper powder and dispersant improve the agglomeration of materials, thereby enhancing the structural properties of the grinding blade, such as strength and hardness.

[0053] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A dicing blade for encapsulating material, characterized by The abrasive material is 40-60 parts by weight, silver powder is 10-15 parts by weight, ultra-fine copper powder is 12-18 parts by weight, conductive whisker is 2-7 parts by weight, carbon nanotube is 1-5 parts by weight, resin powder is 20-30 parts by weight, and dispersant is 0.5-3 parts by weight. The particle size of the ultra-fine copper powder is 0.2-2 μm; the aspect ratio of the carbon nanotube is (5000-15000):1; and the dispersant is nano-rare earth or nano-ceramic.

2. The encapsulation material cutting knife according to claim 1, wherein The abrasive material is diamond, silicon carbide or cubic boron nitride.

3. The encapsulation material cutting knife according to claim 1, wherein The conductive whisker is graphite whisker with a length of 50-100 μm.

4. The encapsulation material cutting knife according to claim 1, wherein The resin powder is phenolic resin powder or epoxy resin powder.

5. A method of producing a dicing blade for encapsulating material according to any one of claims 1 to 4, characterized by, The method comprises the following steps, S1) accurately weighing each material; S2) adding silver powder and ultra-fine copper powder into a mixing tank in sequence, mixing, adding dispersant and mixing uniformly, then adding conductive whisker and carbon nanotube and mixing uniformly, finally adding abrasive material and resin powder and mixing uniformly to obtain a mixture; S3) sieving the mixture, feeding and pressing to obtain a cold-pressed body, wherein the pressure is 2-5 t / cm 2 , and the pressure is maintained for 5-10 s; S4) sintering: placing the cold-pressed blank into a sintering furnace for sintering, taking out after cooling, removing burrs, and obtaining a primary blank, wherein the heating rate is 50-55 ℃ / min, the sintering temperature is 450-600 ℃, and the holding time is 10-20 min; S5) removing burrs by slow wire cutting and processing an inner hole to obtain a blank; S6) processing the blank in a double-end-face thinning machine to obtain a cutting knife for packaging materials.