Thermal Stress
Mechanical stress developed within a material when thermal expansion or contraction is constrained by rigid boundaries.
Governing formula
σ = E α ΔT
SI unit
Pa (N/m²)
In depth
Proportional to Young's modulus $E$, linear thermal expansion coefficient $α$, and temperature change $Δ T$. Unrelieved thermal stress can cause structural fracture.
Examples in the real world
Cracking of thick glass containers when boiling water is suddenly poured into them.