Which type of materials can undergo large strains before they fracture?

Ductile materials are characterized by their ability to undergo substantial plastic deformation before fracture occurs. This property allows them to absorb significant amounts of energy when subjected to stress, making them ideal for applications where durability and impact resistance are crucial.

When ductile materials are stretched or compressed, they do not fracture immediately; instead, they can exhibit considerable elongation or deformation. This behavior is particularly advantageous in situations where sudden failures must be minimized, as ductile materials will often show visible signs of deformation before breaking, giving a warning of impending failure.

In contrast, brittle materials tend to fracture with little to no plastic deformation, while elastic materials return to their original shape after the stress is removed but do not undergo plastic deformation. Viscous materials flow under stress and exhibit time-dependent strain but do not behave like solid materials undergoing typical elastic or plastic deformation scenarios.

Overall, the significant ductility of these materials allows engineers to design structures that can withstand various forces without catastrophic failure, underscoring the importance of ductility in material selection.