ASTM D5034 A Test You Must Know in a Textile Laboratory

The ASTM D5034 test is applied to woven, non-woven, and felted textile fabrics to determine their tensile strength. It determines the fabric’s breaking strength and elongation. This

test is also called the Grab test. It also includes a moderate Grab test, which is not suitable for non-woven fabrics.

Why ASTM D5034 Tensile Strength is Important?

Suppose you are wearing your favorite slim-fit shirt at a party. If you stretch your arms, the shirt tears with an embarrassing sound. Definitely, anyone will feel embarrassed in this situation.

To avoid such issues, tensile test apparatus help textile engineers and manufacturers to develop fabrics that can withstand stress. The tensile strength test evaluates the textile’s strength and durability of test fabrics.

Purpose of Tensile Test

A tensile test’s purpose is to measure the strength of the fabric and to determine how much force a textile fabric can bear before tearing or elongation. It is essential to perform this before shipment if you are a textile testing standards analyst or manufacturer.

This test applies controlled force to the textile fabric to determine its breaking point, elongation in the tensile test, and overall fabric behavior under stress.

The elongation test is applied to woven, nonwoven, and felted textiles. It also includes a moderate grab test, which does not apply to nonwoven fabrics.

ASTM D5034 procedure is not suitable for knitted fabrics, glass fibers, and textiles with a high tensile strength of more than 11%.

Tensile Test Methods     

Tensile tests are generally performed in two ways in cloth testing laboratories.

• Strip Method
• Grab method

In this article, we will discuss the ASTM D5034 Grab test method.

ASTM D5034 Textile Strength and Elongation Grab Test Machine  

To perform this test, here we are taking ASTM D5034 Electronic Strength Machine YG (B) 026HC as a tensile tester by Darong Company China.

ASTM D5034 Textile Strength and Elongation Grab Test Machine YG (B) 026HC

Apparatus and Consumables Required for the Test 

The ASTM D5034 for breaking strength of textile fabric test method requires these apparatus and accessories to perform perfectly.

• Constant rate of tensile testing machine
• Suitable rubber-faced jaws clamping the tensile specimens
• A conditioning room with a temperature of 20 + 2 oC and relative humidity of 65 + 2%

Test Sample Preparation                                           

Before test sample preparation, the textile fabric should be conditioned in a relaxed state for at least 24 hours. To take a specimen, we will take 01-meter full-width fabric.

According to ASTM standards, you must leave the 1oth part of the fabric from the edges to take the sample. For example, if you are taking 60 inches wide fabric, then the sample must be cut 10 inches from the edges of the fabric.

The sample is cut by using the testing template of 100 mm width and a minimum 150 mm length according to testing standards. We will take 05 samples for warp and 08 samples for weft direction.

You should mark the sample for warp (WP) and weft (WT) directions. The test specimen should be cut diagonally from the fabric, leaving a 150-millimeter edge so that the threads should not be in the same direction.

After cutting samples, then mark a jaw alignment line on the specimens before 37 mm from the edges of the sample. Mark the line in full length along the length of the sample on all specimens.

In the Grab method, each test piece should be 100 millimeters wide and long enough to secure a 100-millimetre gauge length.

Now, two sets of test specimens have been prepared. We will evaluate the tensile strength for warp and weft direction separately.

Test Sample Mounting    

The main difference between the Grab test and the strip test is that when doing the strip test, the entire width of the specimen is clamped between the jaws. In a grab test, the center portion of the fabric is clamped to determine its strength.

In the grab test, the back jaw of 25 × 50 mm and the front jaw of 25 × 25 mm are used. Jaws’ faces are coated with rubber with 1.5 mm thickness.

Insert jaw faces into the clamps to provide a clamping area of 25 × 25 millimeters, and the jaw separation will be 100 millimeters.

Universal Testing Machine Tensile Test Procedure         

Now, we are ready to perform the test and evaluate the breaking strength of the test specimen.

1. Before applying the test, we will set the test name and parameters in the software. We will open the testing standard in the search bar and will select ASTM D5034 as a running test.

2. Set the separation of the jaws at 75 mm. Speed is 300 + 10 mm/min. A number of specimens could be according to your requirements.
3. As we start the machine, jaw separation will come at 75 mm.

4. We will select the force unit, Newton. You can change the unit according to your requirements.
5. Start the machine. We are taking warp specimens for testing.
6. The sample should be exactly in the center. It should not be too tight and loose. The specimen should be placed in such a way that its length should be equal on the upper and lower end of the jaws.
7. ASTM D5034 Electronic Strength Machine YG (B) 026HC tensile tester can be operated with a manual button and through the software.
8. As we start the machine, a test will be performed.
9. Similarly same test will be performed for the warp samples.
10. For most European buyer standards, testing a maximum force of 50 kg is satisfactory.
11. Find the average. The average results should be taken separately for warp and weft ways.
12. After that fabric lab test report will be prepared.

Monitor Specimen’s Behavior on Fabric Pull

Two types of tear behavior can be seen during grab test tensile testing.

• Jaw Break 

It means a sample tear within the 5 mm length from the jaw clamp.

• Normal Break 

It means the sample does not tear within the 5 mm length from the jaw clamp. We will save our al results of normal break.

Repeat Test in Case of Mix Break 

Here is the main point that you must monitor while performing this test. If your samples are showing both behaviors, Jaw break, and Normal break, then you must repeat the test.

For example, if you are testing 5-weft samples. If 03 samples show normal break while the other 02 samples show jaw break, then you must repeat the whole test for 05 specimens again.

It will help you to avoid any misleading results.

Difference between Tear and Tensile Strength of Fabric       

Tear and Tensile strength are two important parameters for the physical testing of fabric. Both parameters are used to define the fabric strength but are different in operation and testing.

Tear Strength                                                              

It measures the fabric’s resistance to tear. In this test, force is applied at 90 angles on the fabric to check its tendency to puncture and propagation.

The ASTM standard for tear strength is ASTM D2261.

Tensile Strength 

It measures the fabric’s strength under stress and pull. In this test force is applied horizontally along the fabric to measure elongation and breaking point.

The ASTM standard for tensile strength is ASTM D5034.

What is the difference between ASTM D5034 and ASTM D5035?  

Two ASTM standards are used to determine the tensile test properties, breaking, and elongation of fabric.

1. ASTM D5034 (Grab Test)
2. ASTM D5035 (Strip Test)

Both methods need different sample sizes, having merits and demerits with respect to each other.

ASTM D5034 Grab Test     

In ASTM D5034 smaller size of the sample (100 ×100 mm) or (100 × 150 mm) is clamped in the center and stretched to measure the maximum force that’s fabric can bear under stress.

Grab test uses less sample size, are quicker, and have relatively lower accurate results. There is a chance of a jaw break sample, which may lead to faulty results. That’s why, in this method test needs to be repeated in case of a Jaw break.

ASTM D5035 Strip Test    

In ASTM D5035 relatively larger size sample (50 × 200 mm) is clamped from the ends of the sample in tensile testing jaws. The sample is stretched through the machine and records the maximum force that breaks the specimen from jaws.

This method has the lowest chance of specimen slippage or uneven stretch. The Strip method is considered a more accurate test as compared to the grab test. But it takes more time and a larger sample size.

Both methods are used in textiles to evaluate the tensile strength, elongation, and breaking point. It depends upon the fabric requirements and buyers demand that which test should be done.

These are the ASTM standards for tensile testing of fabrics.

1. ASTM D5034
2. ASTM D5035
3. ASTM D5034 21
4. ASTM D5034 09
5. ASTM D5034 95
6. ASTM D4964

Conclusion  

ASTM D5034 Garb test is performed to measure the tensile strength, elongation, and breaking point of textile fabrics under stress. In ASTM D5034 smaller size of the sample, 100 × 150 mm, is clamped in the center and stretched to measure the maximum force that’s fabric can withstand under stress.

ASTM D5034 09 is not suitable for knitted fabrics, glass fibers, and textiles with a high tensile strength of more than 11%.

FAQs                                           

What is the ASTM D5034 test method?

ASTM D5034 is used to evaluate the tensile strength of textile fabrics. This method is also called the Grap test method. In this test, the specimen is clamped from the center in between two rubber-faced jaws.

A controlled extension force is applied to the fabric to measure the maximum force that which fabric can withstand.

This test determines the breaking point and elongation of the textile fabrics. It also gives the idea about the fabric’s performance under stress.

What should be the sample size for the Grab test?

In the grab test, sample size should be (100 ×100 mm) or (100 × 150 mm).

How many tensile test methods?

There are two methods used for tensile testing in fabric laboratory.

• Stripe method
• Grab method.

Which ASTM standard is known as the Grab test?

ASTM D5034 test for tensile strength is known as the Grab test.

What are the sizes of tensile tester jaws for ASTM D5034?

In the grab test, the back jaw of 25 × 50 mm and the front jaw of 25 × 25 mm are used.

Related Resource

ASTM D5034/ASTM D5035 Electronic Strength Machine YG(B)026HC

What is fabric strength and how to test

A Practical Guidance on ASTM D5035 Breaking Strength and Elongation of Textile Fabrics