For many years, the solid metals and their alloys have been widely used for fabrication of the implants replacing hard human tissues or their functions. To improve fixation of solid implants to the surrounding bone tissues, the materials with porous structures have been introduced. By tissue ingrowing into a porous structure of metallic implant, the bonding between the implant and the bone has been obtained. Substantial pore interconnectivity, in metallic implants, allows extensive body fluid transport through the porous implant. This can provoke bone tissue ingrowth, consequently, leading to the development of highly porous metallic implants, which could be used as scaffolds in bone tissue engineering. The goal of this study was to develop and then investigate properties of highly porous titanium structures received from powder metallurgy process. The properties of porous titanium samples, such as microstructure, porosity, Young's modulus, strength, together with permeability and corrosion resistance were investigated. Porous titanium scaffolds with nonhomogeneous distribution of interconnected pores with pore size in the range up to 600 μm in diameter and a total porosity in the range up to 75% were developed. The relatively high permeability was observed for samples with highest values of porosity. Comparing to cast titanium, the porous titanium was low resistant to corrosion. The mechanical parameters of the investigated samples were similar to those for cancellous bone. The development of high-porous titanium material shows high potential to be modern material for creating a 3D structure for bone regeneration and implant fixation.

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Due to its suitable physical properties and good biocompatibility, the titanium (Ti) can be used for development of porous structures for biomedical applications. The state of art in the field of corrosion resistance showed problems with corrosion analysis of porous metals. Therefore, it is essential to understand the influence of porosity of metals on corrosion parameters. The aim of this study was to investigate the corrosion resistance of highly porous titanium scaffolds for biomedical application. The Ti scaffolds were fabricated by powder metallurgy technique. The total porosity of the scaffolds ranged from 45 to 75%. The cast Ti sample was also tested for comparison. The electrochemical behavior of the Ti samples was monitored by electrochemical impedance spectroscopy (EIS) and potentiodynamic method at the room temperature. All electrochemical experiments were performed by a three-electrode technique in a cell containing a 0.9% NaCl electrolyte solution. With use of AAF, the active area of porous Ti was estimated. The porous Ti with porosity of 75% shows a better resistance to corrosion than the other porous Ti scaffolds. However, the corrosion resistance of Ti scaffolds was lower than cast Ti.

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The main errors of MEMS accelerometers are misalignments of their sensitivity axes, thermal and long-term drifts, imprecise factory calibration, and aging phenomena. In order to reduce these errors, a two-axial tilt sensor comprising a triaxial MEMS accelerometer, an aligning unit, and solid cubic housing was built. By means of the aligning unit it was possible to align the orientation of the accelerometer sensitive axes with respect to the housing with an accuracy of 0.03°. Owing to the housing, the sensor could be easily and quickly recalibrated, and thus errors such as thermal and long-term drifts as well as effects of aging were eliminated. Moreover, errors due to local and temporal variations of the gravitational acceleration can be compensated for. Procedures for calibrating and aligning the accelerometer are described. Values of thermal and long-term drifts of the tested sensor, resulting in tilt errors of even 0.4°, are presented. Application of the sensor for monitoring elevated loads is discussed.

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