Understanding the origin and growth behaviour of cracks in material compounds is a key issue for describing the reliability of electronic components. In order to determine the magnitude and direction of the crack driving force in materials, different fracture mechanics concepts are used. 

The MCL has recently developed the "Configurational Forces" concept further in order to make it easy useable for cracks in layered multimaterial structures. The configurational forces concept in the theory of elasticity goes back to the work of Eshelby in the 1960s. He used the energy-momentum tensor to describe the driving forces on material defects, such as dislocations, interstitial atoms, phase boundaries or crack tips. In the works of Simha et al. and Kolednik et al. the concept was expanded in collaboration with the MCL in order to describe the driving force in heterogeneous structures where residual stresses and plasticity may occur. As a result, this energy-based approach can be generally applied and without restrictions to determine the driving forces for cracks depending on the layered structure architecture, on the elastic and plastic properties of the materials involved and on the residual stresses. 

The material forces concept can be used to increase the damage resistance and the lifetime of the components.

Contact: Werner Ecker