Microstructural development was analyzed due to the effect of different sizes of precursor powders during surface plasma alloying modification on titanium surface. Ti-B nano and micropowders with 10 wt% B were deposit...Microstructural development was analyzed due to the effect of different sizes of precursor powders during surface plasma alloying modification on titanium surface. Ti-B nano and micropowders with 10 wt% B were deposited onto microcrystalline titanium substrate by plasma alloying. As a result, modified surface layer composed of Ti matrix and TiB borides was obtained. The type of the powder precursor influenced recasting process, possible occurrence of porosity and finally the obtained properties and microstructure of the surface layer. Different morphologies and sizes of TiB phase from micro, submicro to even nano increased the hardness and wear resistance of the obtained surface layers. Discussed results referred to a strong TiB precipitation dispersion provided by a fine elements homogenization during mechanical alloying process. Additionally, results of in vitro test with normal human osteoblast cells revealed proper cellular adhesion to modified surfaces. Scanning electron microscopy observation revealed the influence of gas pore size on culturing osteoblast colony. The proposed surface alloying was an effective method of producing TiB phase dispersed in α-Ti matrix with high hardness, good corrosion resistance and good cytocompatibility. Results confirmed that different types of the precursor powders influenced the properties of the surface layer. TiB phase dispersed in α-Ti matrix layer can offer new structural and biofunctional properties for innovative products in hard tissue applications.展开更多
A new kind of biomedical Ti-45S5 Bioglass-Ag nanocomposites and their scaffolds with antibacterial function was developed by the introduction of 1.5 wt% Ag into the Ti-10 wt% 45S5 Bioglass matrix. The microstructure, ...A new kind of biomedical Ti-45S5 Bioglass-Ag nanocomposites and their scaffolds with antibacterial function was developed by the introduction of 1.5 wt% Ag into the Ti-10 wt% 45S5 Bioglass matrix. The microstructure, hardness and corrosion resistance in Ringer solution of the Ag-doped Ti-45S5 glass were investigated. The Vickers hardness of the bulk Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag nanocomposites reached 480 HVo.3. Contact angles of water on the micro- crystalline Ti and nanostructured Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag sample were determined and show visible decrease from 55.2° to 49.6°. In vitro tests culture of normal human osteoblast cells showed very good cells proliferation, colonization and multilayering. In vitro bacterial adhesion study indicated a significantly reduced number of bacteria （Staphylococcus aureus） on the bulk nanostructured Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag plate surface in comparison with that on microcrystalline Ti plate surface. Development of porous Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag scaffolds aims in enhancing bone ingrowth and prosthesis fixation.展开更多
文摘Microstructural development was analyzed due to the effect of different sizes of precursor powders during surface plasma alloying modification on titanium surface. Ti-B nano and micropowders with 10 wt% B were deposited onto microcrystalline titanium substrate by plasma alloying. As a result, modified surface layer composed of Ti matrix and TiB borides was obtained. The type of the powder precursor influenced recasting process, possible occurrence of porosity and finally the obtained properties and microstructure of the surface layer. Different morphologies and sizes of TiB phase from micro, submicro to even nano increased the hardness and wear resistance of the obtained surface layers. Discussed results referred to a strong TiB precipitation dispersion provided by a fine elements homogenization during mechanical alloying process. Additionally, results of in vitro test with normal human osteoblast cells revealed proper cellular adhesion to modified surfaces. Scanning electron microscopy observation revealed the influence of gas pore size on culturing osteoblast colony. The proposed surface alloying was an effective method of producing TiB phase dispersed in α-Ti matrix with high hardness, good corrosion resistance and good cytocompatibility. Results confirmed that different types of the precursor powders influenced the properties of the surface layer. TiB phase dispersed in α-Ti matrix layer can offer new structural and biofunctional properties for innovative products in hard tissue applications.
文摘A new kind of biomedical Ti-45S5 Bioglass-Ag nanocomposites and their scaffolds with antibacterial function was developed by the introduction of 1.5 wt% Ag into the Ti-10 wt% 45S5 Bioglass matrix. The microstructure, hardness and corrosion resistance in Ringer solution of the Ag-doped Ti-45S5 glass were investigated. The Vickers hardness of the bulk Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag nanocomposites reached 480 HVo.3. Contact angles of water on the micro- crystalline Ti and nanostructured Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag sample were determined and show visible decrease from 55.2° to 49.6°. In vitro tests culture of normal human osteoblast cells showed very good cells proliferation, colonization and multilayering. In vitro bacterial adhesion study indicated a significantly reduced number of bacteria （Staphylococcus aureus） on the bulk nanostructured Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag plate surface in comparison with that on microcrystalline Ti plate surface. Development of porous Ti-10 wt% 45S5 Bioglass-1.5 wt% Ag scaffolds aims in enhancing bone ingrowth and prosthesis fixation.
