Two Methods and Instruments of Film Flexibility Test

When evaluating the performance of a film, flexibility is a crucial indicator, which reflects the resilience, plasticity and adhesion of the film under external force. Flexibility testing can help us understand whether the film can maintain its integrity and performance during actual use, as well as its Response to external Impacts. This article will introduce two common methods of flexibility testing, namely the 180 ° bend test using a steel shaft rod and the cone bend tester test, and what these test methods mean in film evaluation.

1. 180 ° bend test of steel shaft rod

According to the GB/T 1731 standard, the Flexibility tester uses a set of steel shaft rods of different thicknesses to check whether the film is cracked by bending the film 180 °. During the test, shaft rods of different diameters, such as 1mm, 2mm, 3mm, 4mm, 5mm, 10mm and 15mm, are used for 180 ° bending. The minimum diameter of the shaft rod without film damage is used to indicate the flexibility of the film.

This test method takes into account the film's resilience, plasticity and adhesion to the substrate. Test results are also affected by factors such as deformation time and speed. Although this method provides an assessment of film flexibility, shafts of different diameters may cause discontinuities in test results.

2. Test of cone bending tester

In order to avoid the discontinuity of test results caused by different axial rod diameters, the conical bending tester becomes another type of flexibility tester. This instrument is specially designed to test the bending performance and flexural strength of materials. It consists of a conical mandrel made of high-quality stainless steel with wear and corrosion resistance. The dimensions of the conical mandrel are 3.1 mm in diameter at the small end, 38 mm in diameter at the large end, and 203 mm in length.

In the test, the sample is placed on the conical mandrel of the cone bending instrument, and the sample is bent and deformed by applying force. By measuring the applied force and the deformation of the sample, the bending performance and bending strength of the material can be determined. This method is simple and easy to operate, and is suitable for bending performance testing of various materials.

Flexibility testing is of great significance in film evaluation. The flexibility of a film determines its Response under external force and whether it can avoid cracking and peeling. This is directly related to the service life, maintenance cycle and Appearance mass of the film. Through the flexibility test, we can understand the performance of the film under different stress conditions, which provides an important basis for the selection and application of the film.

The flexibility of a film is one of the important indicators for evaluating its performance. The flexibility test helps us understand the performance of the film in actual use by evaluating the resilience, plasticity and adhesion of the film under external force. The 180 ° bend test of the steel shaft rod and the test of the conical bend tester are common flexibility test methods, which provide different angles of view to evaluate the performance of the film. These test methods provide valuable information for film selection, application and maintenance.