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Ti6Al4V is one of the most lightweight, mechanically resistant, and appropriate for biologically induced corrosion alloys. However, surface properties often must be tuned for fitting into biomedical applications, and therefore, surface modification is of paramount importance to carry on its use. This work compares the interaction between two different cell lines (L929 fibroblasts and osteoblast-like MG63) and medical grade Ti6Al4V after surface modification by plasma nitriding or thin film deposition. We studied the adhesion of these two cell lines, exploring which trends are consistent for cell behavior, correlating with osseointegration and in vivo conditions. Modified surfaces were analyzed through several physicochemical characterization techniques. Plasma nitriding led to a more pronounced increase in surface roughness, a thicker aluminum-free layer, made up of diverse titanium nitride phases, whereas thin film deposition resulted in a single-phase pure titanium nitride layer that leveled the ridged topography. The selective adhesion of osteoblast-like cells over fibroblasts was observed in nitrided samples but not in thin film deposited films, indicating that the competitive cellular behavior is more pronounced in plasma nitrided surfaces. The obtained coatings presented an appropriate performance for its use in biomedical-aimed applications, including the possibility of a higher success rate in osseointegration of implants.

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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