Charpy V Notch tests measure which property?

• A. Ductility
• B. Hardness
• C. Strength
• D. Toughness

Answer: (D)

Impact toughness is what the Charpy V-notch test measures. This test determines how much energy a material can absorb before it fractures when subjected to a sudden, high-rate load. A notched specimen is struck by a pendulum, and the energy actually absorbed up to fracture is recorded as the impact energy. A higher energy value means the material can withstand greater shock without breaking, which is the essence of toughness. This is different from hardness (resistance to indentation), strength (the load it can bear in tension before yielding or breaking), or ductility (how much it can deform plastically before fracture). The Charpy test specifically assesses a material’s resistance to brittle fracture under impact, capturing its notch toughness. This is particularly important for bridge materials, where low-temperature or rapid loading conditions can cause brittle behavior.