
2.7 OTHER TESTS THAT CAN BE CARRIED OUT ON STEEL REINFORCEMENT
2.7.1 Impact Test
Static tests are not satisfactory in determining the resistance to shock or impact loads such as automobile parts are subject to, and in the impact test a noticed specimen of the material is fracture by a single blow from a heavy hammer, the energy required being a measure of the resistance to impact. The most commonly used type of impact Test Machine is shown in fig 2.11

The specimen whose dimensions are laid down in B.S. 131 is fixed in the anvil with the notch at the level of the top face and on the side of the falling hammer. The hammer is released from a fixed position, such that the total potential energy of fall is 163Nm, strikes the specimen, which breaks and continues for some distance on the other side.
The impact test has been found particularly valuable in revealing “tamper brittleness†in heat-treated nickel chrome steels and also to the resistance to fracture due to stress concentrations in a member.