Plastics Technology Laboratories  

Tensile Testing of Thin Plastic Sheeting


Click on the picture for a larger view

Tensile tests measure the force required to break a specimen and the extent to which the specimen stretches or elongates to that breaking point. Tensile tests produce a stress-strain diagram, which is used to determine tensile modulus. The data is often used to specify a material, to design parts to withstand application force and as a quality control check of materials. Since the physical properties of many materials (especially thermoplastics) can vary depending on ambient temperature, it is sometimes appropriate to test materials at temperatures that simulate the intended end use environment.

Test Procedure:
Specimens are placed in the grips of the Instron and pulled until failure. For ASTM D882 the test speed and grip separation are based on the elongation to break of the material. Elongation and tensile modulus can be calculated from crosshead displacement, or with an extensometer.

Elevated or Reduced Temperature Test Procedure:
A thermal chamber is installed on the Instron universal test machine. The chamber is designed to allow the test mounts from the base and crosshead of the Instron to pass through the top and bottom of the chamber. Standard test fixtures are installed inside the chamber, and testing is conducted inside the controlled thermal environment the same as it would be at ambient temperature. The chamber has internal electric heaters for elevated temperatures and uses external carbon dioxide gas as a coolant for reduced temperatures. The size of the chamber places a limitation on the maximum elongation that can be reached.

Specimen size:
ASTM D882 uses 1" x 6" strips die cut from thin sheet or film.

The following calculations can be made from tensile test results:
  1. tensile strength (at yield and at break)
  2. tensile modulus
  3. strain
  4. elongation and percent elongation at yield
  5. elongation and percent elongation at break

Equipment Used:
Instron Universal Tester

Intertek PTL Overview
Contact Us
Services & Tech Info
Industry Segments
Industry Segments


**Please note that this test description is intentionally generic in nature and aimed at providing a descriptive summary to enhance test understanding. For more information please contact a Intertek PTL Technical Representative at . Due to copyright restrictions, we are not able to provide copies of standards. Standards can be obtained from appropriate standards authorities.

Back to Testlopedia