What are two different types of impact tests?

• A. Izod and Charpy
• B. Rockwell and Brinell
• C. Tensile and Elongation
• D. Izod and Vickers

Answer: (A)

Impact tests measure how much energy a material can absorb before it fractures when hit with a sudden load. The two common types are Izod and Charpy. In both tests, a notched specimen is struck by a swinging pendulum, and the energy absorbed to fracture is recorded. They differ in how the sample is supported and where the notch is located: Charpy uses a horizontally mounted, simply supported bar with the notch in the midsection, struck at the center; Izod uses a cantilever-style fixture with the notch near the end, so the hammer acts on a different portion of the specimen. This changes how the energy is absorbed, but both provide a measure of toughness that can be compared across materials. The other options involve hardness tests (Rockwell, Brinell, Vickers) or a tensile/elongation assessment, which do not measure impact energy.