ASTM D4812 Unnotched test specimens are employed in this test procedure, which sets it apart from others of a similar kind. This test method is especially helpful for reinforced materials because it doesn’t have a notch, which can obscure the effects of orientation. Other filled or unreinforced materials may also be utilized with it if a stress-concentrating notch is not needed. It is not valid for materials that twist when subjected to this test.
The significance of this test method encompasses considerable value for quality assurance and material specification. The fact that a material absorbs twice as much energy as another under certain testing settings does not guarantee that the relationship will remain true under different test conditions.
ASTM D4812 Test Procedure
| Specimen Selection | Unless the sheets are known to be isotropic, specimens for sheet materials must be cut from the sheet both longitudinally and across. The thickness of the sheet must match the width of the test specimen. |
| Test Setup and Execution | The test setup involves using standardized machines equipped with pendulum-type hammers. Standard specimens of the plastic material are carefully positioned for testing. The pendulum is released to swing and strike the specimen, generating flexural shock. The energy extracted from the pendulum is measured, providing an indication of the material’s resistance to breakage. |
