The aim of this study is the investigation of the effect of ferroboron and ferrochromium with massive wire based hardfacing alloys. Mixture of Fe-Cr and Fe-B powders was added to massive wire during welding process. Hardface layers were obtained by three different powder mixture and three different powder/massive wire proportions. Hardfacing was applied to two AISI 1020 steel substrates by open arc welding. Hardness test, scanning electron microscope and X-ray diffraction analysis were made to the samples. Test results showed that increasing ferroboron content and increasing powder mixture amount enhanced the microhardness of the specimens.

People are exposed to different kinds of diseases or various accidents in life. Hydroxyapatite (HA) has been widely employed for bone treatment applications. In this study, HA was extracted from sheep bones. Bio-composites were doped with 1, 5, and 10 wt.% of expanded perlite and 5 wt.% of ZrO2–MgO-P2O5. The bio-composites were prepared by the cold isostatic pressing method (250 MPa) and sintered at 900°C for 1 h. In order to evaluate the characteristics of the bio-composites, microhardness, density, X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses were carried out on them. Additionally, the specimens whose characteristics were determined were kept in synthetic body fluid (SBF), and their in vitro behavior was examined. As a result, it was observed that microhardness increased as both the weight and the grain size of the expanded perlite were increased. Calcium silicate, tri-calcium phosphate, and hydroxyapatite were observed in the XRD analysis of all samples, and the formation of apatite structures was increased by addition of ZrO2–MgO–P2O5.

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: Hydroxyapatite, which is naturally and synthetically available, is often used as a biomaterial because of its similarity to bone. In this study; Natural hydroxyapatite powder, synthesized from sheep bone, and synthetic hydroxyapatite were used as matrix. Hybrid bio-ceramic composites were obtained by adding 5 wt. % expanded perlite-TiO2-ZrO2-MgO-P2O5 to both matrixes. The bio-ceramic materials which were mixed with mechanical mixer for 30 minutes were pressed with hydraulic press under 25 MPa pressure and sintered at 9000C for 1 hour. Density, micro-hardness, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analysis were performed to determine characteristics of the samples. As a result; it was identified that the micro-hardness of natural hydroxyapatite was higher. In addition, the increase in micro-hardness values of ZrO2-reinforced samples was higher than the TiO2-reinforced samples. Hydroxyapatite, calcium silicate, calcium phosphate structures were observed in XRD analysis. Micro-pores were observed in TiO2-reinforced samples while more dense structures were observed in ZrO2-reinforced samples.