Thermal Stress in Electronics
Mechanical stress is a key failure mechanism to consider when designing electronics systems. Excessive mechanical stress can cause cracking, rupture, fatigue, delamination, or even excessive deflection (such as in optical assemblies). Since most electronics systems are not also designed to be a part of the main mechanical load bearing structure, thermal expansion is a primary source of mechanical stress.
CTE (coefficient of thermal expansion) mismatch typically comes to mind when discussing thermal stress, but high-temperature gradients also can cause differential expansion and excessive stress even when the materials are carefully chosen for the best CTE match.
This On-Demand event explores the capabilities of leading simulation software to perform thermal stress analysis. The foundation for any thermal stress analysis is an accurate computation of the conjugate heat transfer situation - a long-time strength of simulation - then the included finite element stress solver can natively compute stresses due to thermal and mechanical loads. Alternatively, STAR-CCM+® can export the temperature field to external stress analysis tools such as NX™ NASTRAN®.