The microstructure, physical and mechanical, and chemical properties of micro-arc calcium phosphate (CAP) coatings deposited under different process voltages in the range of 150-400 V on the commercially pure titani...The microstructure, physical and mechanical, and chemical properties of micro-arc calcium phosphate (CAP) coatings deposited under different process voltages in the range of 150-400 V on the commercially pure titanium (Ti) and Ti-40%Nb (Ti-40Nb) (mass fraction) alloy were investigated by the SEM, TEM, XRD and EDX methods. The coating thickness, roughness, and sizes of structural elements were measured and showed similar linear character depending on the process voltage for the coatings on both substrates. SEM results showed the porous morphology with spherical shape structural elements and rough surface relief of the coatings. XRD and TEM studies exhibited the amorphous structure of the CaP coating. With increasing the process voltage to 300-400 V, the crystalline phases, such as CaHPO4 and β-Ca2P207, were formed onto the coatings. The annealing leads to the formation of complex poly-phase structure with crystalline phases: CaTi4(PO4)6, β-Ca2P2O7, TiP2O7, TiNb(PO4)3, TiO2, NbO2, and Nb2O5. The applied voltage and process duration in the ranges of 200-250 V and 5-10 min, respectively, revealed the coating formed on Ti and Ti-40Nb with optimal properties: thickness of 40-70μm, porosity of 20%-25%, roughness (Ra) of 2.5-5.0 μm, adhesion strength of 15-30 MPa, and Ca/P mole ratio of 0.5-0.7.展开更多
基金Project(III.23.2.5)supported by the Fundamental Research Program of the Siberian Branch of Russian Academy of SciencesProject(15-03-07659)supported by the Russian Foundation for Basic Research+1 种基金Project(CR16-22)supported by the China and Russia on the Implementation of Inter-governmental ScientificTechnological Cooperation Projects of the Notice(NSC foreign word[2012]No.269)
文摘The microstructure, physical and mechanical, and chemical properties of micro-arc calcium phosphate (CAP) coatings deposited under different process voltages in the range of 150-400 V on the commercially pure titanium (Ti) and Ti-40%Nb (Ti-40Nb) (mass fraction) alloy were investigated by the SEM, TEM, XRD and EDX methods. The coating thickness, roughness, and sizes of structural elements were measured and showed similar linear character depending on the process voltage for the coatings on both substrates. SEM results showed the porous morphology with spherical shape structural elements and rough surface relief of the coatings. XRD and TEM studies exhibited the amorphous structure of the CaP coating. With increasing the process voltage to 300-400 V, the crystalline phases, such as CaHPO4 and β-Ca2P207, were formed onto the coatings. The annealing leads to the formation of complex poly-phase structure with crystalline phases: CaTi4(PO4)6, β-Ca2P2O7, TiP2O7, TiNb(PO4)3, TiO2, NbO2, and Nb2O5. The applied voltage and process duration in the ranges of 200-250 V and 5-10 min, respectively, revealed the coating formed on Ti and Ti-40Nb with optimal properties: thickness of 40-70μm, porosity of 20%-25%, roughness (Ra) of 2.5-5.0 μm, adhesion strength of 15-30 MPa, and Ca/P mole ratio of 0.5-0.7.