What happens during 'thermal shock' in materials?

During thermal shock, the key phenomenon is the rapid temperature change that a material undergoes, which can create internal stresses due to uneven expansion or contraction. When a material experiences a sudden temperature change, parts of the material may expand or contract at different rates, leading to tensile or compressive stresses. If the stresses exceed the material's strength or ductility, it can result in cracks or fractures. This situation is especially critical in materials that are brittle, as they do not have the ability to deform plastically to accommodate the stresses induced by temperature changes.

This concept is relevant in various applications, from ceramics and glass to metals, where managing thermal gradients is essential for maintaining material integrity. The other options do not accurately reflect the nature of thermal shock: blending of materials, changes in weight, and enhancements in electrical conductivity do not directly relate to the thermal stress and fracture mechanisms characteristic of thermal shock.