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Izod specimen (on left) and an Charpy specimen (on right).
SRM 2115

ASTM Standard E23 "Standard Test Methods for Notched Bar Impact Testing of Metallic Materials" describes procedures for Izod impact testing (with many similarities to and a few differences from procedures used in Charpy impact testing). The Charpy and Izod specimens have an identical cross section (10 mm by 10 mm) and an identical V notch (located 27.5 mm from one end for Charpy specimens and 28 mm from one end for Izod specimens), but differ in their overall length (55 mm for Charpy and 75 mm for Izod).  

ASTM Standard E23 offers no guidelines for verification of Izod machine performance by test specimens. However, NIST offers this SRM for those who need to check the performance of their Izod machines. The material is heat treated to a high strength, so it has a high resistance to fracture, for only a short period of time. Since the Izod test procedure requires aligning and clamping the specimen in an Izod vise (a relatively slow process) this Izod SRM is tested at room temperature

Created February 12, 2009, Updated August 25, 2016