Which test is used to determine a material's toughness?

Which test is used to determine a material's toughness?

• A. Brinell Hardness Test
• B. Charpy Impact Test
• C. Rockwell Hardness Test
• D. Tensile Test

Answer: (B)

Toughness is the ability of a material to absorb energy and deform without fracturing when exposed to sudden or sharp loads. The Charpy Impact Test directly measures this property by using a notched specimen struck by a pendulum hammer. As the hammer breaks the sample, the machine records the energy absorbed in fracturing the material. More absorbed energy means the material can withstand impact better, while less energy indicates brittleness. The other tests focus on different properties. Hardness tests like Brinell and Rockwell gauge resistance to surface indentation, not how much energy the material can absorb during fracture. The tensile test determines strength and ductility under a steadily applied load, giving yield strength, ultimate tensile strength, and elongation, but it does not directly quantify impact toughness. Hence, the Charpy Impact Test is the standard choice for assessing toughness.

Toughness is the ability of a material to absorb energy and deform without fracturing when exposed to sudden or sharp loads. The Charpy Impact Test directly measures this property by using a notched specimen struck by a pendulum hammer. As the hammer breaks the sample, the machine records the energy absorbed in fracturing the material. More absorbed energy means the material can withstand impact better, while less energy indicates brittleness.

The other tests focus on different properties. Hardness tests like Brinell and Rockwell gauge resistance to surface indentation, not how much energy the material can absorb during fracture. The tensile test determines strength and ductility under a steadily applied load, giving yield strength, ultimate tensile strength, and elongation, but it does not directly quantify impact toughness. Hence, the Charpy Impact Test is the standard choice for assessing toughness.