ISO 148-2:1998 pdf download – Metallic materials — Charpy pendulum impact test — Part 2: Verification of test machines.
3 Definitions For the purposes of this part of ISO 1 48, the following definitions apply. 3.1 Definitions pertaining to the machine 3.1.1 anvil: The portion of the base of the machine forming a vertical plane which restrains the test piece when it is struck by the pendulum (see figures 1 to 3), the plane of the supports being perpendicular to the plane of the anvil. 3.1.2 base: That part of the framework of the machine located below the horizontal plane of the supports. 3.1.3 centre of percussion: That point in a body at which, on striking a blow, the percussive action is the same as if the whole mass of the body was concentrated at the point (see figure 4). NOTE — When a simple pendulum delivers a blow along a horizontal line passing through the center of percussion, there is no resulting horizontal reaction at the axis of rotation. 3.1.4 centre of strike: That point on the striking edge of the pendulum at which, in the free hanging position of the pendulum, the vertical edge of the striker meets the upper horizontal plane of a test piece of half standard height (i.e. 5 mm) or equivalent gauge bar resting on the test piece supports (see figure 2). 3.1.5 industrial machine: Impact machine used for industrial, general, or most research-laboratory testing of metallic materials. These machines are not used to establish reference values. Industrial machines are verified using the procedures described in this part of ISO 1 48. 3.1.6 reference machine: Pendulum impact testing machines used to determine the reference energy of a reference test piece. The verification requirements for this grade of machine are more stringent than those for industrial machines and are contained in ISO 1 48-3.
3.1.7 striker: The portion of the hammer that contacts the test piece. The edge that actually contacts the test piece may have a radius of 2 mm (the 2 mm striker) or a radius of 8 mm (the 8 mm striker). (See figure 2.) 3.1.8 test piece supports: The portion of the base of the machine forming a horizontal plane upon which the test piece rests prior to being struck by the hammer (see figures 2 and 3). The plane of the supports is perpendicular to the plane of the anvil. 3.2 Definitions pertaining to energy 3.2.1 actual absorbed energy (absorbed energy), A V : The total energy required to break a test piece when tested by a pendulum impact testing machine. It is equal to the difference in the potential energy from the starting position of the pendulum to the end of the first half swing during which the test piece is broken (see clause 9). 3.2.2 actual initial potential energy (potential energy), A P : The value determined by direct verification (see clause 9.1 ).