Engineers and researchers who have specialized Charpy testing needs will be the primary users of two new standards recently approved by ASTM International Committee E28 on Mechanical Testing. The new standards, E2248, Test Method for Impact Testing of Miniaturized Charpy V-Notch Specimens, and E2298, Test Method for Instrumented Impact Testing of Metallic Materials, were developed by a task group within Subcommittee E28.07 on Impact Testing.
“Conventional noninstrumented Charpy tests give useful comparative information but generally do not offer any detailed insight into the failure mechanisms or provide quantifiable material properties,” says Enrico Lucon, senior researcher, Institute for Nuclear Materials Science at the Belgian Nuclear Research Center. “Particularly for structural integrity evaluations, using instrumented Charpy impact test data can improve the understanding of failure mechanisms at high loading rates,” notes Lucon. “On the other hand, in the case of thin-walled structures or for optimizing material consumption, miniature Charpy specimens may represent an attractive option.”
Lucon says that instrumenting the machine striker to measure and record the force on the notched sample during impact, as described in E2298, gives a much clearer picture of the events occurring, providing additional insight into the behavior of material under impact loading.
Testing procedures described in E2248 will be helpful for users who need to reduce the size of Charpy specimens either because the investigated component is thin or because the available material is limited in quantity.
Technical Information: Enrico Lucon, SCK-CEN, Belgian Nuclear Research Center, Mol, Belgium
ASTM Staff: Kevin Shanahan