How does the film biaxial stretching apparatus ensure uniform force on the sample during the test?

Publish Time: 2025-03-11

As an important material testing equipment, the film biaxial stretching apparatus is widely used in the mechanical properties testing of thin film materials such as plastics, rubber, and composite materials. During the test, ensuring uniform force on the sample is the key to obtaining accurate and reliable results.

1. Sample preparation and installation

First, the preparation and installation of the sample are important factors affecting the uniformity of force. The sample should be cut strictly according to the standard size and shape to ensure that it can be uniformly stressed during the stretching process. When installing the sample, special clamps should be used. These clamps usually have a self-locking function and can firmly clamp the sample to prevent it from sliding or falling off during the stretching process. In addition, the design of the clamp should ensure the alignment of the sample in the stretching direction to avoid uneven force caused by the skew of the sample.

2. Stretching mechanism design

The stretching mechanism design of the film biaxial stretching apparatus is also the key to ensuring uniform force on the sample. The stretching mechanism is usually driven by a precision servo motor or hydraulic cylinder, which can achieve high-precision stretching speed and force control. At the same time, the stretching mechanism should have a bidirectional synchronous stretching function, that is, it can simultaneously apply uniform tension in two perpendicular directions to simulate the stress state of the film in actual applications. In addition, the stretching mechanism should also have an adjustable stretching ratio and stretching speed to meet the testing needs of different materials.

3. Sensors and control systems

During the test process, sensors and control systems play a vital role. Film biaxial stretching apparatus is usually equipped with high-precision force sensors and displacement sensors, which can monitor the force and deformation of the sample during the stretching process in real time. The control system accurately controls the action of the stretching mechanism according to the feedback signal of the sensor to ensure that the sample is subjected to uniform and stable tension during the stretching process. In addition, the control system should also have an overload protection function to prevent damage to the sample or equipment due to excessive tension.

4. Environmental control and calibration

In addition to the above measures, environmental control and equipment calibration are also key to ensuring uniform stress on the sample. The test environment should maintain a constant temperature and humidity to avoid the impact of environmental changes on the test results. At the same time, regular calibration of the film biaxial stretching apparatus is also an essential step, including calibration of force sensors, displacement sensors, and precision calibration of the stretching mechanism, to ensure the accuracy and reliability of the equipment.

5. Operation specifications and training

Finally, operation specifications and training are also important links to ensure that the sample is evenly stressed. Operators should strictly follow the equipment operation manual to perform test operations to avoid uneven force caused by improper operation. At the same time, regular training and technical guidance for operators to improve their operating skills and troubleshooting capabilities are also important measures to ensure the accuracy and reliability of the test.

In summary, during the test process, the film biaxial stretching apparatus ensures that the sample is subjected to uniform and stable tension during the stretching process through sample preparation and installation, stretching mechanism design, sensors and control systems, environmental control and calibration, and operation specifications and training, thereby obtaining accurate and reliable test results.