Which of the following describes the ability of a material to withstand a sudden change in applied load without breaking?

• A. Hardness
• B. Toughness
• C. Malleability
• D. Brittleness

Answer: (B)

Toughness refers to a material's ability to absorb energy and deform plastically without fracturing. This property is crucial in applications where materials are subjected to sudden changes in load or impact, such as in pipefitting, where components might experience rapid pressure surges or mechanical shocks.

Hardness, while important, specifically measures a material's resistance to deformation, especially permanent deformation or scratching. It does not directly address the ability to absorb energy without breaking.

Malleability describes a material’s capacity to be shaped or deformed under compressive stress, typically without cracking or breaking, but it is focused more on shaping materials rather than their ability to withstand sudden impacts.

Brittleness, on the other hand, characterizes materials that tend to break or shatter easily when subjected to stress or sudden loads, indicating the opposite of toughness.

Thus, toughness is the correct answer as it directly relates to a material's resilience to sudden loads without breaking, which is essential for ensuring reliability and safety in pipefitting applications.