A method for preparing a diamond cutting blade containing a metal bond for cutting BGA packages

Abstract

The present invention discloses a method for preparing a metal-bonded diamond cutting blade for cutting BGA packages. The bonding agent comprises metal powder and ceramic powder with a particle size of 10 to 30 μm, a diamond particle size of 50 to 100 μm, and a concentration of 30 to 80%. The injection molding agent comprises polyethylene, carnauba wax, and stearic acid. Through powder mixing, injection molding, degreasing, and hot pressing, a metal-bonded diamond cutting blade with a thickness of 0.3 mm and a thickness accuracy of ±0.005 mm is produced. The blade effectively reduces side and radial wear, exhibits high machining precision, is sharp, and has a long service life. The yield rate of the product exceeds 95%, and the service life exceeds 3,000 m.

Description

[0001] This invention is a divisional application of Application No. 201711368160.1, Invention Title: A Method for Preparing Metal-bonded Diamond Cutting Blades for Cutting BGA Packages, Applicant: Xi'an Ruining Superhard Tools Technology Co., Ltd. Technical Field

[0002] The invention belongs to the field of abrasive material and grinding tool manufacturing, and particularly relates to a method for preparing a diamond cutting blade containing a metal bond and used for cutting BGA packages. Background Art

[0003] BGA packaging (ball grid array) uses an array of solder balls on the bottom of the package substrate as I / O terminals for interconnection with the printed circuit board (PCB). A key step in the packaging process is ensuring that the dimensions of the packaged chips after cutting meet certain tolerance requirements. Currently, commonly used electroplated and resin cutting blades suffer from rapid side and overall wear, resulting in low product yields and a shortened service life. Summary of the Invention

[0004] The object of the present invention is to provide a method for preparing a diamond cutting blade containing a metal bond for cutting BGA packages, which can effectively maintain the cutting quality of BGA packages and has a long service life.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] (1) Powder mixing: Diamond powder is added to metal and ceramic mixture powders at a volume ratio of 30-80% to obtain a mixture, and then the mixture is added to an injection molding agent at a volume ratio of 60% to obtain a raw material;

[0007] The metal-ceramic mixture powder is composed of 30-35% Cu, 10-20% Ni, 30-35% CuSn20 metal powder with a particle size of 10-30 μm and 8-10% Al2O3, 10-12% SiC ceramic powder with a particle size of 5-30 μm;

[0008] The particle size of the diamond powder is 50-100 μm;

[0009] The injection molding agent is a mixture of polyethylene, carnauba wax and stearic acid in a mass ratio of 40:50:10;

[0010] (2) Injection molding: The raw material is injected into the injection molding machine at a speed of 15-18 kg / cm 2 The pressure is used to press out a blank with a thickness of 0.45-0.55mm;

[0011] (3) Degreasing treatment: Degreasing treatment is carried out at 450-500℃;

[0012] (4) Hot pressing treatment: The degreased blank is placed in a graphite mold and heated from room temperature to 560-580°C at a heating rate of 20°C / min under a pressure of 15 MPa, and then sintered at this temperature for 2.5-3 minutes. Then, the blank is cooled to room temperature at a cooling rate of 45-60°C / min to obtain a diamond cutting blade with a thickness of 0.2-0.3 mm and a thickness accuracy of ±0.005 mm.

[0013] Another object of the present invention is to provide a diamond cutting blade prepared by the above-mentioned method for preparing a diamond cutting blade containing a metal bond for cutting BGA packages.

[0014] This invention uses a metal bond, injection molding, hot pressing, and sintering processes to produce a 0.2-0.3mm thick metal-bonded diamond cutting blade that effectively maintains BGA package cutting quality and offers a long service life. This diamond cutting blade effectively reduces radial and lateral wear and features high machining precision, sharpness, and a long service life. The yield rate exceeds 95%, and the blade has a service life exceeding 3,000 meters. DETAILED DESCRIPTION

[0015] Example 1:

[0016] (1) Powder mixing: Diamond powder with a particle size of 50-100 μm is added to a metal and ceramic mixture powder at a volume ratio of 30% to obtain a mixture, and then the mixture is added to an injection molding agent at a volume ratio of 60% to obtain a raw material;

[0017] The metal-ceramic mixture powder is composed of 30% Cu, 20% Ni, 30% CuSn20 metal powder with a particle size of 10-30 μm and 10% Al2O3, 10% SiC ceramic powder with a particle size of 5-30 μm;

[0018] The injection molding agent is a mixture of polyethylene, carnauba wax and stearic acid in a mass ratio of 40:50:10;

[0019] (2) Injection molding: The raw material is injected into the injection molding machine at a speed of 15 kg / cm 2 The blank with a thickness of 0.55mm is pressed out under the pressure of

[0020] (3) Degreasing treatment: Degreasing treatment is carried out at 450°C;

[0021] (4) Hot pressing treatment: The degreased blank is placed in a graphite mold and heated from room temperature to 560°C at a heating rate of 20°C / min under a pressure of 15 MPa, and then sintered for 3 minutes. Then, it is cooled to room temperature at a cooling rate of 60°C / min to obtain a diamond cutting blade with a thickness of 0.3 mm and a thickness accuracy of ±0.005 mm.

[0022] The diamond cutting blade was used to cut a 0.8mm thick BGA package substrate on a Disco EAD6340K dicing machine. The cutting parameters were: spindle speed 30,000 r / min, feed rate 100 mm / s. The product yield reached more than 98%, and the diamond cutting blade life was 3,500 m.

[0023] Example 2:

[0024] (1) Powder mixing: Diamond powder with a particle size of 50-100 μm is added to a metal and ceramic mixture powder at a volume ratio of 80% to obtain a mixture, and then the mixture is added to an injection molding agent at a volume ratio of 60% to obtain a raw material;

[0025] The metal-ceramic mixture powder is composed of 35% Cu, 10% Ni, 35% CuSn20 metal powder with a particle size of 10-30 μm and 8% Al2O3, 12% SiC ceramic powder with a particle size of 5-30 μm;

[0026] The injection molding agent is a mixture of polyethylene, carnauba wax and stearic acid in a mass ratio of 40:50:10;

[0027] (2) Injection molding: The raw material is injected into the injection molding machine at a speed of 18 kg / cm 2 The blank with a thickness of 0.45 mm is pressed out under the pressure of

[0028] (3) Degreasing treatment: Degreasing treatment is carried out at 500°C;

[0029] (4) Hot pressing treatment: The degreased blank is placed in a graphite mold and heated from room temperature to 570°C at a heating rate of 20°C / min under a pressure of 15 MPa, and then sintered at this temperature for 2.5 min. Then, it is cooled to room temperature at a cooling rate of 45°C / min to obtain a diamond cutting blade with a thickness of 0.3 mm and a thickness accuracy of ±0.005 mm.

[0030] The diamond cutting blade was used to cut a 0.8mm thick BGA package substrate on a Disco EAD6340K dicing machine. The cutting parameters were: spindle speed 30000r / min, feed rate 100mm / s. The product yield reached more than 95%, and the diamond cutting blade life was 3000m.

[0031] Example 3:

[0032] (1) Powder mixing: Diamond powder with a particle size of 50-100 μm is added to a metal and ceramic mixture powder at a volume ratio of 60% to obtain a mixture, and then the mixture is added to an injection molding agent at a volume ratio of 60% to obtain a raw material;

[0033] The metal-ceramic mixture powder is composed of 33% Cu, 15% Ni, 32% CuSn20 metal powder with a particle size of 10-30 μm and 9% Al2O3, 11% SiC ceramic powder with a particle size of 5-30 μm;

[0034] The injection molding agent is a mixture of polyethylene, carnauba wax and stearic acid in a mass ratio of 40:50:10;

[0035] (2) Injection molding: The raw material is injected into the injection molding machine at a speed of 16.5 kg / cm 2 The blank with a thickness of 0.50 mm is pressed out under the pressure of

[0036] (3) Degreasing treatment: Degreasing treatment is carried out at 480°C;

[0037] (4) Hot pressing treatment: The degreased blank is placed in a graphite mold and heated from room temperature to 580°C at a heating rate of 20°C / min under a pressure of 15 MPa, and then sintered at this temperature for 2.5 min. Then, it is cooled to room temperature at a cooling rate of 55°C / min to obtain a diamond cutting blade with a thickness of 0.3 mm and a thickness accuracy of ±0.005 mm.

[0038] The diamond cutting blade was used to cut a 0.8mm thick BGA package substrate on a Disco EAD6340K dicing machine. The cutting parameters were: spindle speed 30,000 r / min, feed rate 100 mm / s. The product yield reached more than 96%, and the diamond cutting blade life was 3,300 m.

[0039] Comprehensive evaluation of the three examples shows that all three can meet the product technical requirements. However, considering the comprehensive performance indicators and actual production, the first example solution is the most effective.

Claims

1. A method for preparing a diamond cutting blade containing a metal bond for cutting BGA packages, characterized in that The following steps are involved: (1) Powder mixing: diamond powder is added to a metal / ceramic mixture powder to obtain a mixture, and then the mixture is added to an injection molding agent to obtain a raw material; the volume ratio of the diamond powder is 30-80%, and the volume ratio of the mixture is 60%; the metal / ceramic mixture powder is composed of a metal powder of 30-35% Cu, 10-20% Ni, and 30-35% CuSn20 with a particle size of 10-30 μm and a ceramic powder of 8-10% Al2O3 and 10-12% SiC with a particle size of 5-30 μm; the particle size of the diamond powder is 50-100 μm; (2) Injection molding: The raw material is pressed into a blank on an injection molding machine; the raw material is pressed into a blank on an injection molding machine at a speed of 15-18 kg / cm 2 The pressure is used to press out a blank with a thickness of 0.45-0.55mm; (3) Degreasing treatment; (4) Hot pressing treatment: The degreased blank is placed in a graphite mold and heated from room temperature to 560-580°C at a heating rate of 20°C / min under a pressure of 15 MPa, and then sintered at this temperature for 2.5-3 minutes. Then, it is cooled to room temperature at a cooling rate of 45-60°C / min to obtain a diamond cutting blade with a thickness of 0.3 mm and a thickness accuracy of ±0.005 mm.

2. The method for preparing a diamond cutting blade containing a metal bond for cutting BGA packages according to claim 1, wherein The injection molding agent comprises polyethylene, carnauba wax and stearic acid, and the polyethylene, carnauba wax and stearic acid are mixed in a mass ratio of 40:50:

10.

3. The method for preparing a diamond cutting blade containing a metal bond for cutting BGA packages according to claim 1, wherein: In the step (3), degreasing treatment is performed at 450-500°C.

4. A diamond cutting blade containing a metal bond for cutting BGA packages, characterized in that: The invention is prepared by the method according to any one of claims 1 to 3.