Impact Test

The notched bar impact test (ASTM E23, BS EN 10045, ISO 148-1 and IS 1757, IS 1598) is a method for evaluating the toughness and notch sensitivity of engineering materials. It is typically used to determine the energy required for the material to deform before fracture, i.e., the toughness of metals, but similar tests are also used for polymers, ceramics, and composites. Metals industries include oil and gas, aerospace, power generation, automotive, and nuclear.

The notched specimen is broken by the impact of a heavy pendulum or hammer falling at a specified speed over a specified distance. During testing, the energy absorbed by the fractured specimen is measured.

Impact test diagram


The test specimen has one, two, or three notches and is machined to have a square or round section. The specimen is positioned on the anvil with the notch facing the hammer and is secured vertically.


A test specimen with either a “V” or “U” notch is machined to a 10mm x 10mm (full size) cross-section. Where there are limitations on material thickness, sub-size specimens are used. Cryogenic temperatures can be used to evaluate samples.

Standards we tested to

Sr No

Discipline: Impact Test

Test Methods


Charpy U Notch
Impact Test

ASTM E23: 2018, IS 1499: 2003, IS 1757-1: 2020, ISO 148-1: 2016


Charpy V Notch Impact Test

ASTM E23: 2018, ASTM A370: 2022, ISO 148-1: 2016


Izod Impact Test

IS 1598: 2020

Impact izod