Thermal shock is characterized by which phenomenon?

• A. A slow, uniform heating
• B. A gradual deformation
• C. Fracture due to chemical corrosion
• D. The fracture of the material as a result of a rapid temperature change

Answer: (D)

Thermal shock arises when a material experiences a rapid temperature change, causing surface layers to expand or contract much faster than the interior. This creates large internal stresses due to thermal gradients; if these stresses exceed the material’s strength, cracks form and the piece fractures. This is especially true for brittle materials like glass and ceramics that can’t easily plastically accommodate sudden stresses. Slower, uniform heating doesn’t produce the same abrupt stresses, and fracture due to chemical corrosion involves reactions rather than rapid mechanical stress from temperature change.