Crack propagation in Low Temperature Co-fired Ceramics underbiaxial loading

Low Temperature Co-fired Ceramics (LTCCs) are layered ceramic basedcomponents, which – in recent years - are increasingly used as electronic devices (e.g. mobileand automotive technologies) in highly loaded (temperatures, inertia forces, etc.)environments. They consist of a complex three-dimensional micro-network of metal structuresembedded within a glass-ceramic substrate. In many cases, LTCC components are exposed tomechanical stresses, which may lead to crack propagation within the part. In this regard,different types of failure of the end component during service have been reported, comingfrom different parts within the component.In this work, the mechanical response of LTCC components has been investigated underbiaxial loading, aiming to reproduce a common scenario during service. The influence of theinternal architectures of the LTCCs on the crack propagation has been assessed in10 × 10 mm2 specimens using the ball-on-three-balls test and evaluated using Weibullstatistics. Fractography of broken specimens has been performed to determine the mode offracture of the components and the role of the internal architecture in the crack path. Resultsshow strength dependence as a function of the testing position within the part, which shouldbe taken into account for the realisation of more reliable designs.