Primary investigations of the electrochemical micromachining process supported by electrode ultrasonic vibrations have been carried out. As a result the basic characteristic of this process and optimal process parameters for which surface roughness is minimal have been found. It has been proved that electrode ultrasonic vibrations help to decrease the surface roughness parameter R a in comparison to the classical electrochemical process. The analyses of phenomena occurring in the machined area and indications for further investigations have been also presented.

Selective laser melting technology makes it possible to produce 3D cellular lattice structures with controlled porosity. The paper reflects to machining and examination of structures with predefined distribution, shape and size of the pores. In the study, the porous structures of Ti6Al4V were investigated. The tests were carried out using structures of spatial architecture of Schwarz D TPMS geometry with a total porosity of 60% and 80% and various pore sizes. Dimensional accuracy of additively manufactured structures was measured in relation to the 3D model. Geometry of the final structure differed from the CAD model in the range ± 0.3 mm. The surface morphology and porosity of the solid struts were also checked. The mechanical properties of the structures were determined in a static compression test.

Abstract. Construction of metallic implants with a porous structure that mimics the biomechanical properties of bone is one of the challenges of orthopedic regenerative medicine. The selective laser sintering technique (SLS) allows the production of complex geometries based on three-dimensional model, which offers the prospect of preparing porous metal implants, in which stiffness and porosity can be precisely adjusted to the individual needs of the patient. This requires an interdisciplinary approach to design, manufacturing and testing of porous structures manufactured by selective sintering. An important link in this process is the ability to assess the surface topography of the struts of porous structure. The paper presents a qualitative assessment of the surface morphology based on SEM studies and methodology that allows for quantitative assessment of stereometric structure based on micro-tomographic measurements.Key words: metal porous implant, selective laser sintering, surface roughness, X-ray microtomography.Morphology and surface topography of Ti6Al4V lattice structure fabricated by selective laser sintering tain an implant with a defined pore structure. An alternative to traditional methods of manufacturing metallic porous material is rapid prototyping by selective laser sintering (SLS) or selective electron beam melting (EBM). The ability to produce complex geometric shapes based on three-dimensional CAD model allows for precise control of not only the product geometry itself, but also of shape, size and distribution of pores in the proposed structure.Taking into account requirements set for porous medical implants, design, manufacturing and testing of porous structures manufactured by SLS require an interdisciplinary approach. An important role in this process is played, among other things, by verification of the accuracy of the porous implant 3d geometry and the evaluation of the surface topography of the struts. Nowadays a large number of instruments for measuring surface roughness is available [12]. Most often they operate on the basis of the profile method. Data is collected based on the points arranged in a line or based on image registration from different positions. The choice of specific method is determined by the purpose and conditions of measurement [13,14]. The measurement of surface roughness inside the porous structures manufactured by selective laser sintering is practically not achievable (without destroying the object) by conventional methods. An alternative is constituted by x-ray microtomography. The authors' [15, 16] work studies have shown that in case of a relatively large surface roughness (micro-scale) a comparable, or even better accuracy can be achieved using the mentioned method than with conventional measuring methods. For the measurements of small surface roughness (sub-micronscale) limitation may constitute spatial resolution of the images and noise. The aim of this study is to investigate the morphology and the surface topography of the Ti6Al4V porous structure produc...

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The corrosion of materials used in the design of metal-air batteries may shorten their cycle life. Therefore, metal-based materials with enhanced electrochemical stability have attracted much attention. The purpose of this work was to determine the corrosion resistance of commercially pure titanium Grade 2 (CpTi G2) cellular lattice with the triply periodic minimal surfaces (TPMS) architecture of G80, D80, I-2Y80 in 0.1 M KOH solution saturated with oxygen at 25 °C. To produce CpTi G2 cellular lattices, selective laser melting technology was used which allowed us to obtain 3D cellular lattice structures with a controlled total porosity of 80%. For comparison, the bulk electrode was also investigated. SEM examination and statistical analysis of the surface topography maps of the CpTi G2 cellular lattices with the TPMS architecture revealed much more complex surface morphology compared to the bulk CpTi SLM. Corrosion resistance tests of the obtained materials were conducted using open circuit potential method, Tafel curves, anodic polarization curves, and electrochemical impedance spectroscopy. The highest corrosion resistance and the lowest material consumption per year were revealed for the CpTi G2 cellular lattice with TPMS architecture of G80, which can be proposed as promising material with increased corrosion resistance for gas diffusion in alkaline metal-air batteries.