Ti–Nb–Ta–Zr alloys for biomedical applications were successfully fabricated by arc melting(AM) and diffusion bonding.The microstructure, mechanical properties and electrochemistry behavior in a simulated body fluid...Ti–Nb–Ta–Zr alloys for biomedical applications were successfully fabricated by arc melting(AM) and diffusion bonding.The microstructure, mechanical properties and electrochemistry behavior in a simulated body fluid(SBF) were studied.It shows that melted Ti–Nb–Ta–Zr alloy mainly contains β phase although there are a few Ti-rich phases and micropores, the number of which is lower than that in sintered sample with a few Ti-rich and Ta-rich phases.The melted alloys present higher strength(1224 MPa), Young’s modulus(15.3 GPa) and corrosion potential(-0.34 V) in SBF, while total recovery strain ratio(67.5%) and pseudoelastic strain ratio(8.4%) of sintered Ti–Nb–Ta–Zr alloy keep higher value than 35.7%and 5.0% for melted Ti–Nb–Ta–Zr.The reasons were discussed based on the microstructure of the Ti–Nb–Ta–Zr alloys.展开更多
Bioactive calcium phosphate coatings were prepared on AZ91D magnesium alloy in phosphating solution in order to im- prove the corrosion resistance of the magnesium alloy in Simulated Body Fluid （SBF）. The surface mo...Bioactive calcium phosphate coatings were prepared on AZ91D magnesium alloy in phosphating solution in order to im- prove the corrosion resistance of the magnesium alloy in Simulated Body Fluid （SBF）. The surface morphologies and compo- sitions of the calcium phosphate coatings deposited in the phosphating bath with different compositions were investigated by Scanning Electron Microscopy （SEM） with Energy Dispersive Spectrometer （EDS） and X-ray Diffraction （XRD）. Results showed that the calcium phosphate coating was mainly composed of dicalcium phosphate dihydrate （CaHPO4o2H20, DCPD）, with Ca/P ratio of approximately 1 ： 1. The corrosion resistance was evaluated by acid drop, electrochemical polarization, elec- trochemical impedance spectroscopy and immersion tests. The dense and uniform calcium phosphate coating obtained from the optimal phosphating bath can greatly decrease the corrosion rate and hydrogen evolution rate of AZ91D magnesium alloy in SBE展开更多
Bone-like nanohydroxyapatite powders (b-nanoHA) were synthesized in simulated body fluid (SBF). The b-nanoHA, gelatin (Gel) and Polyvinyl Alcohol (PVA) were used to prepare bone-like composites (b-nanoHA/ Gel/PVA) at ...Bone-like nanohydroxyapatite powders (b-nanoHA) were synthesized in simulated body fluid (SBF). The b-nanoHA, gelatin (Gel) and Polyvinyl Alcohol (PVA) were used to prepare bone-like composites (b-nanoHA/ Gel/PVA) at room temperature. Characterizations of b-nanoHA powders and b-nanoHA/Gel/PVA composites were investigated by using X-ray diffraction (XRD), transmission electron microscopy (TEM), High-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Bending strength and compressive strength of the composite were tested. It was found that microstructure of the b-nanoHA powders was whisker shape and its crystalline degree was low similar to natural bone, bending strength and compressive strength of the b-nanoHA/Gel/PVA composite depended on the mixing ratio of HA, Gel and PVA, and also PVA could induce the network formation in the b-nanoHA/Gel/ PVA composite.展开更多
基金financially supported by the Natural Science Foundation of Shanxi Province (No.201801D221095)the Maker Team Program from Jinzhong University of Shanxi Province in China (No.1331)
文摘Ti–Nb–Ta–Zr alloys for biomedical applications were successfully fabricated by arc melting(AM) and diffusion bonding.The microstructure, mechanical properties and electrochemistry behavior in a simulated body fluid(SBF) were studied.It shows that melted Ti–Nb–Ta–Zr alloy mainly contains β phase although there are a few Ti-rich phases and micropores, the number of which is lower than that in sintered sample with a few Ti-rich and Ta-rich phases.The melted alloys present higher strength(1224 MPa), Young’s modulus(15.3 GPa) and corrosion potential(-0.34 V) in SBF, while total recovery strain ratio(67.5%) and pseudoelastic strain ratio(8.4%) of sintered Ti–Nb–Ta–Zr alloy keep higher value than 35.7%and 5.0% for melted Ti–Nb–Ta–Zr.The reasons were discussed based on the microstructure of the Ti–Nb–Ta–Zr alloys.
文摘Bioactive calcium phosphate coatings were prepared on AZ91D magnesium alloy in phosphating solution in order to im- prove the corrosion resistance of the magnesium alloy in Simulated Body Fluid （SBF）. The surface morphologies and compo- sitions of the calcium phosphate coatings deposited in the phosphating bath with different compositions were investigated by Scanning Electron Microscopy （SEM） with Energy Dispersive Spectrometer （EDS） and X-ray Diffraction （XRD）. Results showed that the calcium phosphate coating was mainly composed of dicalcium phosphate dihydrate （CaHPO4o2H20, DCPD）, with Ca/P ratio of approximately 1 ： 1. The corrosion resistance was evaluated by acid drop, electrochemical polarization, elec- trochemical impedance spectroscopy and immersion tests. The dense and uniform calcium phosphate coating obtained from the optimal phosphating bath can greatly decrease the corrosion rate and hydrogen evolution rate of AZ91D magnesium alloy in SBE
文摘Bone-like nanohydroxyapatite powders (b-nanoHA) were synthesized in simulated body fluid (SBF). The b-nanoHA, gelatin (Gel) and Polyvinyl Alcohol (PVA) were used to prepare bone-like composites (b-nanoHA/ Gel/PVA) at room temperature. Characterizations of b-nanoHA powders and b-nanoHA/Gel/PVA composites were investigated by using X-ray diffraction (XRD), transmission electron microscopy (TEM), High-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Bending strength and compressive strength of the composite were tested. It was found that microstructure of the b-nanoHA powders was whisker shape and its crystalline degree was low similar to natural bone, bending strength and compressive strength of the b-nanoHA/Gel/PVA composite depended on the mixing ratio of HA, Gel and PVA, and also PVA could induce the network formation in the b-nanoHA/Gel/ PVA composite.
