Thermomechanische

Thermomechanische, or thermomechanical, is a term used in engineering and physics to describe the study of how thermal and mechanical phenomena interact in materials and structures. It encompasses how temperature changes induce stresses and strains, how mechanical deformation affects heat flow, and how material properties evolve with temperature. Key areas include thermoelasticity, thermo-viscoelasticity, phase transformations under thermal conditions, creep, fatigue, and thermal shock resistance.

The core idea is to couple the equations of heat transfer with those of solid mechanics. The temperature field T(x,t) influences material stiffness, expansion, and rate processes, while mechanical fields modify heat generation and transport. In linear isotropic thermoelasticity, the stress tensor σ relates to the strain ε and temperature rise ΔT by a constitutive relation such as σ = C:[ε − α ΔT I], where C is the elastic stiffness tensor, α is the coefficient of thermal expansion, and I is the identity tensor. The governing equations include balance of linear momentum and energy balance, solved together with appropriate boundary and initial conditions.

Applications span engineering design and manufacturing, including welded joints, castings, turbine blades, electronic components, and additive manufacturing, where thermal gradients produce residual stresses. In geophysics, thermomechanical models describe mantle convection and rock deformation. Computationally, thermo-mechanical analyses are performed with finite element methods to simulate coupled heat and mechanical fields. Experimental methods include thermo-mechanical analysis (TMA), dilatometry, and dynamic mechanical analysis under controlled temperature, used to characterize material behavior across temperatures.