The purpose of tearing experiment of electronic universal testing machine is to find the tearing strength value. The rubber products with or without cuts are stretched continuously at the prescribed speed until the rubber pattern is torn, so that the tearing strength value can be obtained. The tear strength is generally related to specimen shape, tensile speed and test temperature. Below is a brief sharing of the electronic universal testing machine for various shapes of specimens tear test knowledge.

1. Choose right-angled specimens without notches: The right-angled specimens without notches are a combination of tear initiation and tear propagation. The stress at the right-angle point rises to suffice for initial tearing, and then increases further until the specimen is torn. However, only the total force required to destroy the specimen can be measured. Therefore, the measured force can not be decomposed into two components which produce tear initiation and tear propagation.

2. The crescent-shaped specimen is selected by the electronic universal testing machine: the crescent-shaped specimen is pre-cut to determine the force required for the expansion tear of the specimen. The cutting, measurement and test of the specimen should be carried out continuously. If the test cannot be carried out continuously, the specimen should be saved to the test under the specified temperature test according to the specific conditions. The interval between the cut and the test should not exceed 24 hours. In addition, when aging test is carried out, the cut and the cut should be in line after aging. It should be noted that the specimen should be cut from the uniform specimen with the thickness of (2.0 (+0.2) mm. The specimen can be made by moulding or cutting and grinding the product.

3. Selection of trousers-shaped specimen: trousers-shaped specimen is insensitive to the length of the cut, while the other two samples require strict control of the cut. In addition, the results obtained are more likely to be related to the basic tearing ability of the material, but less affected by the constant tensile stress (generally neglected), and the tearing propagation speed is directly related to the tensile speed of the gripper.

4. The electronic universal testing machine chooses the right-angled specimen with cutting edge: the right-angled specimen with cutting edge is to cut the specimen beforehand to determine the force required for its expansion tearing, but it should be noted that the direction of the tearing edge should be consistent with the direction of calendering, because the expansion speed has no direct relationship with the tensile speed, and is related to the cutting mode and calendering direction of the specimen.

The above is to share the electronic universal testing machine for various shapes of specimens tear test knowledges, I hope you can bring help, if you want to know more about the testing machine details, you are welcome to pay attention to Jinan Kairui, here not only to provide you with high-quality testing machine equipment, but also to provide a variety of equipment information, to help you further understand the equipment. If there is any demand, you are welcome to consult.