What is the tear strength of the fabric? What is acceptable?

Have you ever had an embarrassing situation where your clothes were snapped off by sharp objects? In real life, our clothes snap and tear when worn, which involves strong tearing of the fabric. So what is the tear strength?

fabric tear

Fabric tearing, also known as tearing, applies a concentrated load to local yarns of the fiber to tear the fabric apart. In the process of using the fabric, the clothes are caught by objects, and part of the yarn is pulled apart by force, causing the fabric to form strips or triangular cracks, which is also a phenomenon of fracture.

tear strength

It can reflect the degree of catalysis of the finished fabric, so the tear strength test is performed on pure or blended combed fabrics formed of resin-finished cotton fabrics and wool. Knitted fabrics are generally not subject to tear testing unless otherwise specified.

How to judge whether the tear strength of clothes is qualified?

There are several methods of tear strength testing:

1. Pendulum

2. Pants method (including single-tongue method and double-tongue method)

3. Trapezoidal method

4. Wing method.

A common test method is the trouser-type single-tongue tear test. and how to test it?

The standard requires that each sample be cut into two test samples. One is vertical. The other is horizontal. Each test sample shall include at least 5 pieces. Then test it.

When the stressed yarns in the sample gradually separate upwards and downwards, the yarns that are not directly stressed begin to slide relative to the stressed yarns and gradually draw closer to form an approximate triangular region, usually called the stressed yarn triangle.

Sliding is limited due to the frictional resistance between the yarns, that is, the number of yarn roots in the stressed triangle is limited. In the stress triangle region, the stress at the base of the first yarn is the largest, and then decreases continuously.

As it slides, the tension in the yarn increases rapidly, as does the elongation of the yarn. When the first yarn constituting the base edge of the force triangle triangle is deformed to the elongation at break, the yarn breaks. This results in a certain maximum value for the tear load. Then the next yarn starts to become the bottom edge of the force triangle, so the yarns of the non-draw system break one at a time, tearing the fabric.

Finally, the electronic computing unit divides the first peak and the last peak into four regions, excluding the first region, and records all peaks in the remaining three regions. Calculate the average and record the tear strength for that sample. (The unit is represented by N)