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Multilayer ceramics based on Low‐Temperature Co‐fired Ceramics (LTCC) are gaining increasing interest in the manufacturing of high‐integrated devices for microelectronic and sensor applications. In many applications the parts are exposed to mechanical stresses, which is an important issue regarding the reliability of the device. To predict the lifetime of LTCC multilayer devices, and to extend their application range, basic mechanical data of this material are needed. In this paper metallized LTCC multilayers are investigated concerning their flexural strength, crack growth rate, and lifetime prediction. The results show that the electronic layout concerning the location of vias and metallization has a strong influence on the reliability and lifetime prediction of such co‐fired LTCC devices. Mass flow sensors for the measurement of injected fuel quantities, which were fabricated on the basis of LTCC and which are exposed to a stress level of 100 MPa, achieve sufficient lifetimes. Therefore, LTCC is an interesting material to fabricate devices, in which LTCC fulfils the requirements of a functional and structural material.

In Figure 6 the elastic constants and the strength dependent on the fiber-to-loading deviation are shown. It becomes obvious that the model describes the experiments very accurately.Conclusions: Based on the continuum damage mechanics and a plasticity model which is linked to the progress of damage it is possible to describe the mechanical behavior of ceramic matrix composites with weak and porous matrices under tensile loading with different fiber orientation. The investigated C/C material behaves strongly anisotropic due to the reinforcement by a two-dimensional fiber weave. Damage tolerant mechanical behavior and high strain to failure is realizable due to the low modulus and strength of the matrix. The critical damage processes and failure mechanisms are evaluated by quasistatic tensile tests with different fiber orientations which are well described by the proposed model. This model allows now to predict the material behavior in any other loading direction. The conformity of experimental and theoretical results shows the capability of the model which can now be applied for other composites with porous matrix and strong fibers.The feasibility of a nondestructive microwave inspection to detect internal processing defects in low pressure injection moulded ceramic parts was investigated. A b-TCP (b-tricalcium phosphate, Ca 3 (PO 4 ) 2 ) slurry with paraffin, ethylene vinyl acetate copolymer and stearic acid as binder system was injection moulded with a pressure of 0.2 MPa and subse- COMMUNICATIONS