The paper deals with the experimental study of laser beam micromachining of the powder metallurgy processed Ti compacts applying the industrial grade fibre nanosecond laser operating at the wavelength of 1064 nm. The influence of the laser energy density on the surface roughness, surface morphology and surface elements composition was investigated and evaluated by means of surface roughness measurement, scanning electron microscopy (SEM), energy dispersive X-Ray spectroscopy (EDS) and X-ray diffraction (XRD) analysis. The different laser treatment parameters resulted in the surfaces of very different characteristics of the newly developed biocompatible material prepared by advanced low temperature technology of hydride dehydride (HDH) titanium powder compactation. The results indicate that the laser pulse energy has remarkable effects on the machined surface characteristics which are discussed from the point of view of application in dental implantology.

Deoxidized oxygen free copper C12200, 1 mm in thickness, was welded to 1-mm thick AISI 304 stainless steel with disk laser. The butt-welded joints were produced with different welding parameters. Full factorial design of experiment (DoE) approach consisting of three factors and two levels was utilized. Laser powers used for welding were 1.3 and 1.9 kW and welding speeds of 20 and 30 mm/s. Two beam offsets were tested, namely, 100 μm toward copper side and 200 μm toward AISI 304 steel. It was found that beam offset possesses the largest influence on the welded joints’ tensile strength. Tensile strengths attained values more than 3.7 times higher in comparison to the AISI 304 steel beam offset. When lower laser power was used, the higher tensile strength was attained for copper sheet offset. Higher microhardness was observed when laser beam was offset to AISI 304 steel side. The average microhardness of the weld metal was higher than that of the weaker base material, copper sheet. Energy dispersive X-ray spectroscopy (EDS) analysis confirmed the heterogeneity in elemental composition across the welded joint interface, being lower when laser beam was offset to AISI 304 steel side. On the other hand, the copper content dropped to the average composition of weld metal at the distance of about 140 μm from copper-weld metal interface.

Biocompatible materials with excellent mechanical properties as well as sophisticated surface morphology and chemistry are required to satisfy the requirements of modern dental implantology. In the study described in this article, an industrial-grade fibre nanosecond laser working at 1064 nm wavelength was used to micromachine a new type of a biocompatible material, Ti-graphite composite prepared by vacuum low-temperature extrusion of hydrogenated-dehydrogenated (HDH) titanium powder mixed with graphite flakes. The effect of the total laser energy delivered to the material per area on the machined surface morphology, roughness, surface element composition and phases transformations was investigated and evaluated by means of scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), confocal laser-scanning microscopy (CLSM) and X-ray diffraction analysis (XRD). The findings illustrate that the amount of thermal energy put to the working material has a remarkable effect on the machined surface properties, which is discussed from the aspect of the contact properties of dental implants.

The paper examines the surface functionalization of a new type of Ti-graphite composite, a dental biomaterial prepared by vacuum low-temperature extrusion of hydrogenated-dehydrogenated titanium powder mixed with graphite flakes. Two experimental surfaces were prepared by laser micromachining applying different levels of incident energy of the fiber nanosecond laser working at 1064 nm wavelength. The surface integrity of the machined surfaces was evaluated, including surface roughness parameters measurement by contact profilometry and confocal laser scanning microscopy. The chemical and phase composition were comprehensively evaluated by scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction analyses. Finally, the in vitro tests using human mesenchymal stem cells were conducted to compare the influence of the laser processing parameters used on the cell’s cultivation and osteo-differentiation. The bioactivity results confirmed that the surface profile with positive kurtosis, platykurtic distribution curve and higher value of peaks spacing exhibited better bioactivity compared to the surface profile with negative kurtosis coefficient, leptokurtic distribution curve and lower peaks spacing.

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In this study the relationship between laser beam machining parameters and machined surface quality, applying nanosecond pulsed ytterbium fibre laser (wavelenght 1064 nm, maximal average output power 100 W) and aluminium bronze (AMPCO 25 ®) as working material, is experimentally studied. The laser micromilling was performed via the cross hatching milling strategy. The influence of the laser pulse intensity, scanning speed and laser track distance on the machined surface morphology formation and surface roughness parameters was evaluated using ANOVA (Analysis of Variance). Finally, the machining quality was evaluated by means of SEM micrographs. The results show that the laser pulse intensity played the most significant role on the final surface morphology formation. It was also documented only negligible influence of the laser track distance on the final surface roughness.

The field of biocompatible material surfaces is a widely researched topic. Surface energy, surface topography and surface chemistry are important properties of biocompatible surfaces. These properties contribute to better osseointegration and adhesion of cells to implant surfaces. This article investigates the chemical and phase composition of the surface of a new titanium composite produced by powder metallurgy. Surface oxidation of the graphite– titanium metal matrix composite (TiMMC) after laser beam micromachining (LBMM) is discussed in this paper. Laser micromachining was performed in an argon shielding atmosphere and air. The aim was to determine the influence of the shielding atmosphere and the input parameters of LBMM on the presence of oxygen on the surface. Laser-treated surfaces were examined with scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The phase composition was analysed with X-ray diffraction (XRD). Experiments confirmed that an argon shielding atmosphere reduces surface oxidation. The oxidation was also affected by the energy of the laser beam acting on the material. The maximum amount of oxygen detected on the surface after LBMM in air and argon was 38.6 wt. % and 24.2 wt. %, respectively. The presence of TiO, TiO2 and Ti2O3 oxides were detected on the surface after laser ablation in air. In contrast, Ti2O3 and TiO oxides were detected after laser ablation in the argon shielding atmosphere.

Experimental results for solar metallurgy, solar powder metallurgy of titanium, solar surface treatment of titanium and titanium welding are briefly reviewed. Most of them were performed at Plataforma Solar de Almeria Spain using solar furnaces SF5 and SF40 in gas/vacuum furnace. Generally, it was observed that the time to achieve required sample temperature is very short when concentrated solar power used. Thanks to use of renewable solar energy these technologies starts to be attractive for industrial production of titanium in Earth solar belt. It can be expected that the obtained results and approaches are similar also in Space. According to the obtained knowledge, the possible solutions/necessary changes for solar furnaces on Moon, Mars and in main asteroids belt are discussed.