ASTM D624

To properly characterize thermoset rubbers, thermoplastic elastomers and silicones, knowledge of their rupture properties is essential. A common failure of these materials known as tear is a mechanical rupture process that is initiated and propagated at a site of high stress concentration caused by a cut, defect, or a localized deformation. The tears can be further classified as smooth or knotty, and represent a unique characteristic of any particular material. The ASTM D624 test standard outlines the test method procedures for measuring tear strength of conventional vulcanized rubber and thermoplastic elastomers.

 

In this procedure, a tearing strain (stress) is applied to a test specimen using a universal testing machine operating at a constant rate of crosshead travel until the specimen is completely torn. We know that tear strength is largely influenced by stress-induced anisotropy (also called mechanical fibering), stress distribution, strain rate, and test piece size. Therefore the results obtained in a standard tear strength test should only be regarded as one measure under the conditions of that particular test, and may differ from that material’s actual in-service performance.

 

Solutions for ASTM D624 typically include these types of components:

 

Both the premium MTS Criterion® and the economical MTS Exceed® universal testing machines are ideal for testing of vulcanized rubber and thermoplastic elastomers per ASTM D624. These test systems come in a variety of force capacities and frame styles, ranging from 1-column tabletops to larger 2-column floor-standing models. The 30kN and 100kN models also have dual-zone test spaces to reduce set-up times if you frequently change test requirements. And as an alternative to a new load frame, you can modernize the software and controls of your old test system with an MTS ReNew™ Upgrade.