WO2017107585A1

WO2017107585A1 - Method for evaluating mechanical property of metal-based copper foil-coated laminated board

Info

Publication number: WO2017107585A1
Application number: PCT/CN2016/099128
Authority: WO
Inventors: 佘乃东; 黄增彪; 吕吉; 张华�
Original assignee: 广东生益科技股份有限公司
Priority date: 2015-12-22
Filing date: 2016-09-14
Publication date: 2017-06-29
Also published as: CN105445118B; CN105445118A

Abstract

A method for evaluating a mechanical property of a metal-based copper foil-coated laminated board comprises the following steps: (1) providing a to-be-tested metal-based copper foil-coated laminated board; (2) preparing to-be-tested samples: cutting the metal-based copper foil-coated laminated board into two groups of to-be-tested samples of a same size, and etching parts of copper foils of the to-be-tested samples; bending the parts of one group of the to-be-tested samples provided with copper foils, by a preset angle around a cylinder having a preset diameter, the other group of the to-be-tested samples serving as blank samples and being not bent; (4) carrying out voltage resistance testing on the two groups of to-be-tested samples; and (5) comparing voltage values capable of being borne by the two groups of to-be-tested samples, namely the to-be-tested samples and the blank samples, the samples being qualified when an average value of voltage resistance values is maintained above 80%. By means of the method, internal defects of a bent metal substrate can be recognized, the bending capability of the metal substrate can be quantitatively and effectively evaluated, and a mechanical property of the to-be-tested metal-based copper foil-coated laminated board can be simply, rapidly and conveniently evaluated.

Description

Method for evaluating mechanical properties of metal-based copper-clad laminate

Technical field

The invention belongs to a method for evaluating mechanical properties, and in particular relates to a method for evaluating mechanical properties of a metal-based copper-clad laminate.

Background technique

With the mass production of electronic information products and the trend towards light, short, and versatile, the printed circuit board, which is mainly supported by electronic components, is also being improved with the technical level to provide high-density wiring, thin, and fine aperture. High heat dissipation. In the background, a high-heat-dissipation metal-based copper-clad laminate was born. LED is the main application field of metal-based copper-clad laminates. In order to improve the light-emitting effect, a curved-mounted LED has been proposed, and the bendable metal-based copper-clad laminate used for it has been required to be bent.

The bonding and bendability of metal-based copper-clad laminates is a major indicator affecting its application, including the adhesion of copper foil and bonding layer, the adhesion of metal substrates and bonding layers, and stickiness. The bendability of the layer, there is a clear method for evaluating the adhesion of the copper foil and the bonding layer, such as testing the peel strength of the copper foil, but this method is not suitable for evaluating the adhesion of the metal substrate and the bonding layer. The bonding force, the toughness of the bonding layer, and the bendability of the metal base of the metal-clad copper clad laminate.

CN 12539318A is used to observe the delamination of the bonding layer without the copper sample to be tested after bending. If no delamination occurs, it indicates that the sample to be tested meets the test requirements, and if delamination occurs, it indicates that the sample to be tested does not meet the test requirements. In order to evaluate whether the mechanical properties of the CCL are in compliance with the test requirements. However, the test method can not be judged by observing an accurate quantitative evaluation, for example, the internal defect which occurs after the bonding layer is bent, and it is not a copper test sample, and the bending property of the entire metal substrate cannot be distinguished. Moreover, the test method is a qualitative assessment and quantitative assessment cannot be achieved.

Summary of the invention

In view of the problems of the prior art, the object of the present invention is to provide a method for evaluating the mechanical properties of a metal-based copper-clad laminate, which can distinguish the internal defects after the metal substrate is bent, and can quantitatively and effectively evaluate the metal substrate. The bending ability enables simple and quick evaluation of the mechanical properties of the metal-clad copper-clad laminate to be tested.

In order to achieve the above object, the present invention adopts the following technical solutions:

A method for evaluating the mechanical properties of a metal-based copper-clad laminate comprises the following steps:

(1) providing a metal-based copper clad laminate to be tested (Fig. 1);

(2) Making a sample to be tested: cutting the metal-based copper-clad laminate into two sets of samples of equal size and etching part of the copper foil of the sample to be tested (Fig. 2);

(3) bending a portion of the sample to be tested with a copper foil around a cylinder of a predetermined diameter to a predetermined angle (see FIG. 3), and another set of test samples as a blank sample without bending;

(4) Performing withstand voltage tests on two sets of test samples;

(5) Comparing the voltage values that the two groups of test samples can withstand, the average value of the withstand voltage value of the sample to be tested is more than 80%.

The invention can quickly distinguish the internal defects after the metal substrate is bent, and quantitatively and effectively evaluate the bending ability of the metal substrate. The bendable ability according to the present invention refers to the sample pressure level retention rate before and after bending.

Preferably, the metal comprises a metal substrate such as an aluminum base, an iron base or a copper base.

Preferably, a portion of the copper foil of the sample to be tested is etched away to form a pattern of copper foil, the pattern comprising a circle or a square, preferably a circle.

Part of the copper foil is etched on the sample to be tested. The distance between the edge of the etched copper foil and the edge of the plate is determined according to the applied voltage value. Preferably, the distance between the edge of the etched copper foil and the edge of the plate is not less than 5 mm.

Preferably, the bending is such that the copper foil pattern of the sample to be tested is bent outward.

Preferably, when the sample to be tested is bent, it is bent by a three-point bending device or a bending instrument; the three-point bending device includes a replaceable cylinder; the bending instrument includes the cylinder at one end The rotating shaft of the body rotates around the central axis thereof, and the sample to be tested is bent on the outer peripheral surface of the cylinder of the rotating shaft.

Preferably, the cylinder has a radius of 1-100 mm, such as 2 mm, 3 mm, 5 mm, 7 mm, 9 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 Millimeter, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm or 95 mm, by varying cylinders of different diameters to achieve different bending radii.

Preferably, the bending angle is 30-180, such as 35, 38, 40, 45, 50, 55, 60, 70, 80, 90, 100, 120 , 140°, 150°, 160°, 170° or 180°.

Preferably, the number of samples of the two sets of test samples is 3-10 pieces per group, for example, 4 pieces, 5 pieces, 6 pieces, 7 pieces, 8 pieces or 9 pieces per group, and the sample quantity of the sample to be tested is comparable. The number of samples in a blank sample is the same or more than the number of samples in a blank sample.

Preferably, the sample to be tested has a size of 20-100 mm, such as 22 mm, 25 mm, 28 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm. , 70 mm, 75 mm, 80 mm, 85 mm, 90 mm or 95 mm, 50-250 mm long, eg 53 mm, 55 mm, 58 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 90 mm, 100 mm, 110 mm, 130 mm, 150 mm, 180 mm, 200 mm, 220 mm or 240 mm.

Preferably, the voltage withstand test is performed by connecting the two ends of the electrode to the copper foil surface and the metal base surface of the sample to be tested, and applying a voltage, and the applied voltage is a direct current voltage or an alternating current voltage.

Preferably, when the voltage withstand test is performed, the set voltage value is 100-6000V, for example, 120V, 200V, 400V, 500V, 1000V, 1200V, 1500V, 1800V, 2000V, 2200V, 2500V, 2800V, 3000V, 3300V, 3500V, 3800V, 4000V, 4300V, 4500V, 4800V, 5000V, 5400V or 5800V, set the leakage current to 0.1-20mA, such as 0.2mA, 0.3mA, 0.5mA, 1mA, 1.5mA, 2mA, 3mA, 4mA, 5mA, 8mA, 10mA, 13mA, 15mA or 18mA.

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

The method for evaluating the mechanical properties of the metal-based copper-clad laminate provided by the invention can distinguish the internal defects after the metal substrate is bent, and can quantitatively and effectively evaluate the bendability of the metal substrate, and realize the simple and quick evaluation of the metal-based copper-clad foil to be tested. The mechanical properties of the laminate.

DRAWINGS

Figure 1 is a metal-based copper clad laminate, wherein 1-copper foil, 2-bonded layer, 3-metal base;

Figure 2 is a metal-based copper clad laminate etched away from a portion of the copper foil, 1-etched copper foil remaining, 2-bonded layer, 3-metal base;

Figure 3 is a test sample after bending, the remaining copper foil after 1-etching is patterned, 2-bonded layer, 3-metal base, 4-cylinder

detailed description

The technical solution of the present invention will be further described below by way of specific embodiments.

Example 1

The metal-based copper clad laminate A to be tested was cut into 6 samples of a width of 100 mm and a length of 100 mm, and the intermediate copper foil of the sample to be tested was etched into a circle having a diameter of 50 mm.

The samples to be tested are divided into two groups (A1 and A2), each group of 3, the A2 sample copper surface is facing outward and bent by 90° according to the bending radius of 2 mm, and the bent A2 sample and the unbent The A1 sample was subjected to a withstand voltage test, and the DC voltage was set to 5000 V and the leakage current was 0.1 mA. The sample of group A1 can withstand a voltage value of 5000V. 5000V, 5000V; A2 group samples can withstand voltage values of 5000V, 5000V, 5000V; record the actual withstand voltage values of the two groups of samples, the sample pressure level before and after bending does not decrease (retention rate 100%), the material is resistant to bending Good ability.

Example 2

The metal-based copper clad laminate B to be tested was cut into six samples to be tested having a width of 100 mm and a length of 100 mm, and the intermediate copper foil of the sample to be tested was etched into a circle having a diameter of 50 mm.

The samples to be tested are divided into two groups (B1 and B2), each group of 3, the B2 sample copper surface is facing outward and bent by 90° according to the bending radius of 2 mm, and the bent B2 sample and the unbent The B1 sample was subjected to a withstand voltage test, and the DC voltage was set to 5000 V and the leakage current was 0.1 mA. The sample of B1 can withstand the voltage value of 5000V, 5000V, 5000V; the sample of B2 can withstand the voltage value of 3500V, 3000V, 3000V; record the actual withstand voltage value of the two groups of samples, and the average retention value of the sample withstand voltage after bending At 63% (retention rate less than 80%), the sample withstand voltage decreased by more than 20% after bending, and was unqualified.

Example 3

The metal-based copper clad laminate C to be tested was cut into six samples to be tested having a width of 100 mm and a length of 100 mm, and the intermediate copper foil of the sample to be tested was etched into a circle having a diameter of 50 mm.

The samples to be tested are divided into two groups (C1 and C2), each group of 3, the copper surface of the C2 sample is turned outward and bent by 90° according to the bending radius of 2 mm, and the bent C2 sample and the unbent The C1 sample was subjected to a withstand voltage test, and the DC voltage was set to 5000 V and the leakage current was 0.1 mA. The sample of C1 can withstand the voltage value of 5000V, 5000V, 5000V; the sample of C2 can withstand the voltage value of 4500V, 4200V, 4500V; record the actual withstand voltage value of the two groups of samples, the average value of the sample withstand voltage after bending For 88% (retention rate is greater than 80%), the sample withstand voltage drop after bending is less than 20%, qualified.

Example 4

The metal-based copper clad laminate D to be tested is cut into 6 pieces having a width of 100 mm and a length of A sample of 100 mm in size is sampled, and the intermediate copper foil of the sample to be tested is etched into a circle having a diameter of 50 mm.

The samples to be tested are divided into two groups (D1 and D2), each group of 3, the D2 sample copper surface is facing outward and bent by 90° according to the bending radius of 2 mm, the bent D2 sample and the unbent The D1 sample was subjected to a withstand voltage test, and the DC voltage was set to 5000 V and the leakage current was 0.1 mA. The D1 group can withstand voltage values of 5000V, 5000V, 5000V; the D2 group can withstand voltage values of 1500V, 1500V, 1800V; record the actual withstand voltage values of the two groups of samples, and the average value of the sample withstand voltage after bending When it is 32% (retention rate is less than 80%), the sample withstand voltage drops after bending is greater than 20%, which is unqualified.

Comparative example 1

The same metal-based copper clad laminate B of Example 2 was cut into six samples to be tested having a width of 100 mm and a length of 100 mm, and the intermediate copper foil of the sample to be tested was etched into a circle having a diameter of 50 mm.

The samples to be tested are divided into two groups (B1 and B2), each group of 3, the B2 sample copper surface is facing outward and bent at a bending radius of 2 mm by 90°, and the B2 sample after bending is observed and unbent. For the B1 sample, no difference in the bending position was found.

Comparative example 2

The same metal-based copper clad laminate C of Example 3 was cut into six samples to be tested having a width of 100 mm and a length of 100 mm, and the intermediate copper foil of the sample to be tested was etched into a circle having a diameter of 50 mm.

The samples to be tested are divided into two groups (C1 and C2), each group of 3, the copper surface of the C2 sample is turned outward and bent by 90° according to the bending radius of 2 mm, and the C2 sample after bending is observed and unbent. For the C1 sample, no difference in the bending position was found.

Comparative example 3

The same metal-based copper clad laminate D of Example 4 was cut into six samples to be tested having a width of 100 mm and a length of 100 mm, and the intermediate copper foil of the sample to be tested was etched into a circle having a diameter of 50 mm.

Divide the sample to be tested into two groups (D1 and D2), each group of 3, and place the D2 sample with the copper surface facing outward and press 2mm. The bending radius was bent by 90°, and the D2 sample after bending and the unfolded D1 sample were observed, and it was found that the bent B2 of the D2 sample had a partial crack.

Comparative example 4

The same metal-based copper clad laminate D of Example 4 was cut into six samples to be tested having a width of 100 mm and a length of 100 mm, and the copper foil of the sample to be tested was completely etched away.

The samples to be tested are divided into two groups (D1 and D2), each group of 3, the D2 sample bonding layer is facing outward and bent by 90° according to the bending radius of 2 mm, and the D2 sample after bending and bending is observed and unbent. The D1 sample was folded and no difference in the bending position was found.

The Applicant declares that the present invention is described by the above-described embodiments, but the present invention is not limited to the above detailed methods, that is, it does not mean that the present invention must be implemented by the above detailed methods. It should be apparent to those skilled in the art that any modifications of the present invention, equivalent substitution of the various materials of the products of the present invention, addition of auxiliary components, selection of specific means, and the like, are all within the scope of the present invention.

Claims

A method for evaluating mechanical properties of a metal-based copper-clad laminate, characterized in that the method comprises the following steps:

(1) providing a metal-based copper clad laminate to be tested;

(2) Making a sample to be tested: cutting a metal-based copper-clad laminate into two groups of samples of equal size and etching, and etching part of the copper foil of the sample to be tested;

(3) bending a portion of the sample to be tested with a copper foil around a cylinder of a predetermined diameter for a predetermined angle, and another set of test samples as a blank sample without bending;

(4) Performing withstand voltage tests on two sets of test samples;

(5) Comparing the voltage values that the two groups of test samples can withstand, the average value of the withstand voltage value of the sample to be tested is more than 80%.
The method for evaluating the mechanical properties of a metal-based copper-clad laminate according to claim 1, wherein the metal base of the metal-clad copper-clad laminate comprises any one of an aluminum base, an iron base or a copper base.
The method for evaluating the mechanical properties of a metal-based copper-clad laminate according to claim 1 or 2, wherein the portion of the copper foil of the sample to be tested is etched away to form a certain copper foil pattern, the graphic comprising Round or square.
The method for evaluating the mechanical properties of a metal-based copper-clad laminate according to claim 3, wherein the pattern is circular.
The method for evaluating the mechanical properties of a metal-based copper-clad laminate according to any one of claims 1 to 3, wherein the distance between the edge of the etched copper foil and the edge of the rim is not less than 5 mm.
The method for evaluating the mechanical properties of a metal-based copper-clad laminate according to any one of claims 1 to 5, wherein the bending is such that the copper foil pattern of the sample to be tested is bent outward.
The method for evaluating the mechanical properties of a metal-based copper-clad laminate according to any one of claims 1 to 6, characterized in that, when the sample to be tested is bent, it is bent by a three-point bending device or a bending instrument. The three-point bending apparatus includes a replaceable cylinder; the bending apparatus includes a rotating shaft having the cylinder at one end, the rotating shaft is rotated about a central axis thereof, and the sample to be tested is on the outer peripheral surface of the cylinder of the rotating shaft Bend up.
The method for evaluating the mechanical properties of a metal-based copper-clad laminate according to any one of claims 1 to 7, wherein the cylinder has a radius of 1-100 mm and is replaced by replacing cylinders of different diameters. Different bending radii.
The method for evaluating the mechanical properties of a metal-based copper-clad laminate according to any one of claims 1 to 8, characterized in that the bending angle is 30-180°.
The method for evaluating the mechanical properties of a metal-based copper-clad laminate according to any one of claims 1 to 9, wherein the number of samples of the two sets of test samples is 3-10 per group;

Preferably, the sample to be tested has a size of 20-100 mm in width and 50-250 mm in length.
The method for evaluating the mechanical properties of a metal-based copper-clad laminate according to any one of claims 1 to 10, wherein the voltage withstand test is performed by connecting both ends of the electrode to the copper foil surface of the sample to be tested and A voltage is applied to the metal base and the applied voltage is a direct current voltage or an alternating current voltage.
The method for evaluating the mechanical properties of a metal-based copper-clad laminate according to any one of claims 1 to 11, characterized in that the voltage value is set to 100-6000 V and the leakage current is 0.1-20 mA when the withstand voltage test is performed. .