What is ASTM D 638 standard test method for tensile properties of plastics?

 

 

1. Selection of specimens: Standard size specimens are cut from plastic products, depending on the type of plastic being evaluated and the test requirements.

 

2. Prepare the specimen: according to the requirements of the standard, carry out the necessary surface treatment on the specimen, such as trimming the edges, removing defects that may affect the test results.

 

3. Mounting the specimen: the specimen is clamped in the fixture on the tensile testing machine, ensuring that the specimen is correctly aligned and tightened.

 

4. Starting the test: the specimen is loaded at a constant rate, usually a certain rate of stretching per minute. During the test, the force and displacement or extension of the specimen are measured and recorded.

 

5. Calculation of mechanical property parameters: Based on the force and displacement data obtained from the test, different mechanical property parameters such as tensile strength, yield strength, modulus of elasticity, elongation, etc. are calculated.

 

6. analysis and reporting: data analysis based on the test results, and in accordance with the standard requirements to summarise and report the relevant mechanical property parameters.

 

When performing ASTM D638 testing, ensure that the standard requirements are adhered to, including preparation of specimens, control of test conditions, and calibration of equipment. This ensures that test results are accurate and comparable so that they can be used for material selection, quality control, product development, and specification compliance.

 

It should be noted that the ASTM D638 standard can have different variants, such as D638 Type I, Type II, Type IV, etc., each of which has different requirements for specimen size and test conditions. The applicable version and variant of the standard should be carefully read and followed before testing is performed.