Tensile Properties (Sheet) ASTM D882

Scope:
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 Universal Tester 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 Universal Test machine. The chamber is designed to allow the test mounts from the base and crosshead of the Universal Tester 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.

Data:
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:
Universal Tester

**Please note that this test description is intentionally generic in nature and aimed at providing a descriptive summary to enhance test understanding. Standards can be obtained from appropriate standard authorities.