TIM performance with gap movement

Thermal interface materials (TIMs) are indispensable for the efficient cooling of electronic and mechatronic systems. Particularly in applications with different thermal expansion coefficients of the components, TIMs are subject to high thermomechanical stress, which is a frequent cause of failure for complete assemblies.

A typical example is the bulging of electrical modules due to mechanical stresses. The TIM used must reliably compensate for the resulting gap expansions. The suitability of a material for such challenges can be specifically tested using the so-called elongation test. It tests how a TIM behaves under defined gap expansion and at what point adhesive or cohesive failure occurs.

An important test parameter here is the effective thermal resistance and its change. The measurement is carried out using the stationary cylinder method in accordance with ASTM D5470 on our ZFW TIM Tester.