Copper Clad Laminate Peeling Test

  1. Copper Clad Laminate 90° Peel Test

Abstract: This article introduces the use of the Kunpeng BOYI 2025 electronic universal testing machine, equipped with a 500N pneumatic dual push-pull tensile fixture and a 90° peel fixture, to conduct a copper clad laminate 90° peel test according to Section 2.4.8 - Peel Strength of Copper Clad Laminates in the IPC-TM-650 Test Methods Manual. The peel strength characterizes the adhesion strength between the copper layer and the substrate. Test results show that the Kunpeng BOYI 2025 electronic universal testing machine fully supports the 90° peel test of copper clad laminates.

Keywords: Kunpeng BOYI 2025 electronic universal testing machine, copper clad laminate, 90° peel test

Copper Clad Laminate (CCL) is a sheet material made by impregnating electronic fiberglass cloth or other reinforcing materials with resin, then laminating one or both sides with copper foil and hot pressing. CCL is an important base material for PCBs. With the development of the electronic information industry, copper clad laminate technology has been widely applied alongside PCB technology. One important technical indicator of CCL is the adhesion strength of the copper layer. The higher the adhesion strength, the more stable the connection between the copper layer and the substrate, reducing the likelihood of peeling or detachment. Adhesion strength is characterized by peel strength. This application introduces the 90° peel strength test of copper clad laminates.  
The Kunpeng testing machine is equipped with a pneumatic dual push-pull tensile fixture and a 90° peel fixture, enabling quick positioning and clamping of samples before testing and easy repositioning after testing, improving operational convenience and testing efficiency, greatly saving test time. During the peel test, thanks to the high-precision slide rail and synchronization device of the dedicated 90° peel fixture, the board and the testing machine axis maintain a constant 90° angle, ensuring the test process meets standard requirements. Besides the fixtures, the main testing machine's high precision and data acquisition frequency exceeding 1000Hz can fully record all characteristic data during the peel process, providing users with accurate and reliable test data. Coupled with intelligent testing software, it can simultaneously provide various test curves such as single sample, multiple samples, and dual coordinates, offering a good interactive experience for different users and safeguarding enterprises' R&D, quality, and product control.

1. Experimental Section

1.1 Instruments and Fixtures

BOYI 2025-001 Electronic Universal Testing Machine

500N Pneumatic Dual Push-Pull Tensile Fixture

90° Peel Fixture

Smartest Software

1.2 Analysis Conditions

Test Temperature: Approximately 25°C (room temperature)

Load Sensor: 1000N (Class 0.5)

Loading Test Rate: 50.8 mm/min

1.3 Samples and Treatment

In this test, samples with a fixed adhesion width of 3.18 mm were selected, and the copper foil surface was reinforced with special tape. The samples were pre-peeled to a certain distance, ensuring the peeled end had good adhesion between the copper foil and tape to avoid delamination or edge damage, ensuring no breakage during peeling. The peeled end length was sufficient to be fully clamped by the upper fixture. The peel test requires the testing machine fixture clamping end to maintain a 90±5° angle with the substrate during peeling.

2. Test Introduction

The test was conducted using the BOYI 2025-001 electronic universal testing machine. The sample was mounted on the 90° peel fixture, with the copper foil clamped in the upper fixture and the substrate clamped in the lower fixture, forming a 90° peel state as shown below (Figure 1). The test was performed at a rate of 50.8 mm/min. Force and displacement data during the peel process were measured. The average peel force during the low peel force state was taken to obtain peel force and peel strength data (Table 1), and peel curves were generated (Figures 2-3).

Figure 1 Test System Diagram (Main Machine, Fixtures)

3. Results and Conclusions

3.1 Test Results

After the test, the load-displacement curves of the sample's 90° peel test are shown in (Figures 2-3). During peeling, subtle force fluctuations were captured by the main machine, forming stable peel curves. Using the testing software, load and displacement data can be obtained from the curves, along with the average peel strength. Specific test results are as follows (Table 1).

Transverse

Longitudinal

Figure 2 90° Peel Curve (Multiple Samples)

Figure 3 90° Peel Curve (Single Sample)

Figure 4 Sample Peel State

From the data in (Table 1) and the post-peel sample state, it can be seen that throughout the test, the sample peeling was stable with very little fluctuation and no abnormal peeling phenomena. The average values of two groups of five samples each were very close, with the difference between maximum and minimum values within 0.1 N/mm. This test result reflects the high precision and high stability of the Kunpeng BOYI 2025-001 electronic universal testing machine.

4. Conclusion

In summary, the Kunpeng BOYI 2025-001 electronic universal testing machine, 500N pneumatic dual push-pull tensile fixture, and 90° peel fixture fully meet the requirements of Section 2.4.8 - Peel Strength of Copper Clad Laminates in the IPC-TM-650 Test Methods Manual, efficiently and effectively completing the test. Through a high-precision, high-sampling-rate testing system, various mechanical data of copper clad laminates can be obtained reliably and stably. This is very important for the technological development of the copper clad laminate and PCB industries, providing data support and technical assurance for enterprises' product R&D, quality management, and industry standardization and regulation.