DENG Chi
,
WANG Yong
,
ZHANG Yaping
,
GAO Jiacheng
钢铁研究学报(英文版)
Titanium alloy has been a successful implant material owing to its excellent ratio of strength to weight, toughness, and bioinert oxide surface. Significant progress has been made in improving the bioactivity of titanium alloy by coating its oxide surface with calcium phosphates. In the present study, in situ coating was reported on Ti6Al4V(TC4) surface with calcium phosphate (CaP) bioceramics synthesized and synchronously cladded by laser beam. This coating was grown by first preplacing directly the raw powders, which contain 80% of CaHPO4·2H2O, 20% of CaCO3, and dram of rare earth (RE), on the TC4 surfaces, and then exposing the surfaces to the laser beam with a power density of 1273-1527 MW·m-2 and a scanning velocity of 105 m/s. The resultant coating was characterized using scanning electron microscopy (SEM), Xray diffraction (XRD), thermogravimetric analysis and Differentthermal Scanning (TGDSC), and Energy Dispersive Xray Detection (EDX). The results show that these laser ceramics include hydroxyapatite (HA), tricalcium phosphate (TCP), Ca2P2O7, and other CaP phases, and the interface between the coating and the TC4 substrate has tighter fixation, in which the chemical bonding is approved. These laser hybrid coatings are useful in enhancing the bioactivity of titanium alloy surfaces.
关键词:
titanium alloy surface;calcium phosphate ceramics;laser cladding;bioactivity